UPDATE 17 April: If you are using NBI for your install, the backlight-not-returning-after-sleep issue has been resolved by ronin510. He figured out that editing one line in the included AppleIntelIntegratedFramebuffer.kext to match a different version that was updated (or wasn't updated) in 10.6.3 will fix the sleep issue. See his instructions here.
UPDATE 13 March: It has been reported that the new pre-release version of the NetbookInstaller (0.8.4) is problematic. Avoid it unless you're into debugging and alpha testing. Also, please note that installing NBI or Enabler during installation is now NOT necessary! You can just restart after the installation finishes, but leave BOTH USB keys connected until OSX has booted into the desktop for the first time, then install NBI/Enabler like normal. This should also help you avoid getting the "mach_kernel" error.
UPDATE 6 March: As it turns out, we don't need to bother with installing the Enabler or the NetbookInstaller while still in the installation process. We can get into OSX on the first boot without them. As such, the guide has been modified to reflect this, cutting out all of the Terminal commands and leaving it up to the user to download and install whichever patch method they prefer after first boot. Special thanks to ronin510 for setting me straight.
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THIS GUIDE IS STILL IN PROGRESS. By the time it's published, it will be complete as far as content, but the formatting will be made better in the next couple of days. I know my writing is lengthy and wordy, but I want to be sure I'm clear when I'm giving directions (I'm a teacher, it's my thing). I will try to bullet-point as much as I can. I'll also clean up and mirror the links wherever possible. Consider this a rough draft.
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This guide will take you through the steps to easily install Snow Leopard to your S10 using only Windows tools and two USB drives. It allows for installation on MBR hard disks, which opens the door for easy dual-booting with XP, Linux, and Windows 7 - although those topics will have to wait for another guide. This one is just for a clean, retail installation of OS X 10.6.
Highlights:
-This method uses only Windows software for all preparation - no Mac needed for pre-install work!
-This method was written for MBR hard disks, but you can skip that step if you are sticking with GUID.
-This method has only been tested on the S10 Classic - there is plenty of post-install info for other systems elsewhere.
-This method was tested as a clean install on a clean hard drive, but it could be done using just a single partition (no guarantees on the ease of that route).
-This method will guide you through the initial boot. Anything beyond that falls under "post-install" discussions.
-This method will provide instructions for installing with either vaniii's SL Enabler or the NetbookInstaller. Your choice.
Alrighty, let's get started.
Required hardware:
Two USB flash drives - One 8gb or larger and one 64mb or larger.
A computer running Windows for the prep work (the S10 will work).
A DVD drive to make a disk image of your retail Snow Leopard install DVD.
Your S10 with enough hard drive space for a full installation - at least 10gb recommended.
Required software:
-Windows (of course).
-TransMac - I used the latest version 9.1 on my Windows 7 machine, but earlier versions should also work.
-Your retail Snow Leopard install DVD (or the backed up .dmg of said DVD if you already have one).
-Modified OSInstall.mpkg and OSInstall files for MBR installation (skip if you're trying GUID).
-NetbookInstaller disk image (even if you're using the Enabler, you need this for booting the DVD).
-The Snow Leopard Enabler OR NetbookInstaller app (latest versions recommended - don't get the NetbookBootMaker, you want the NetbookInstaller). UPDATE: You can actually wait on these until after first boot, no need to have them on your installation media beforehand as long as you have wifi access to download them in OSX once you're logged in. If you don't, you may want to get them ahead of time and put them on a USB stick. I just copied them onto the large Install USB key using TransMac, but there have been reports of trouble doing this in other tests.
The process:
First, you need to install TransMac to your Windows system. They offer a 15-day free trial, or you can buy it and support the cause. When it is installed, launch it and click the "Options" menu, then check "Show Hidden Files."
After that, the first thing you need is a .dmg image of your retail Snow Leopard DVD. Insert your DVD, launch TransMac, and right-click on the DVD in the menu pane. Select "Save image of disk" and save it to your hard drive as a .dmg image. If you already have the .dmg image, make sure it is expanded (you may have compressed it when you made it) and move to the next step.
Now it's time to make your installation USB from the DVD image. Connect the larger USB drive to your machine. When it shows up in TransMac, right-click on it and select "Format disk" and then "Format with Disk Image." In the windows that pops up, navigate to the .dmg of your DVD and select it. The process will take a few minutes.
NOTE: I had some trouble with a pre-formatted USB key, I actually had to delete the FAT32 partition on the volume using the Windows Disk Management application and let TransMac format the unformatted drive itself.
Once the large drive has been formatted, you'll need to modify it a bit so it will install to an MBR drive. Open the MBR Patch folder on your desktop. In TransMac, click on the new HFS+ volume on your large USB drive and navigate to /System/Installation/Packages. Drag-and-drop the OSInstall.mpkg from the MBR Patch folder into the main window of TransMac to copy it to the USB drive (it will overwrite the original file). Then do the same to copy the OSInstall file to /System/Library/PrivateFrameworks/Install.framework/Frameworks/OSInstall.framework/Versions/A/. Again, overwrite the previous version.
Connect your smaller USB key to your Windows machine (again, unformatted). Right-click it in TransMac and select "Format disk" and "Format with Disk Image," just like before. This time, select the NBI_083F.img file. It should be done pretty quick. This is now your boot stick.
And now, we install OSX!
Reboot your system with both USB keys connected. When the Lenovo splash screen shows up, hit F2 quickly to enter the BIOS setup. Change the boot order if necessary so that the S10 boots from all USB devices first, the the internal HDD. Plug both USB keys in and save/exit the BIOS setup. When it reboots again, hit FN+F11 (the F12 key) to get to the boot device selection screen (sometimes you don't know which USB port will boot first, and you need to boot from the right device to launch the installation). Select your smaller USB key and your system should launch a Chameleon bootloader.
Select the Mac OS X Install DVD from the menu to launch the installer. Once it boots up, enter Disk Utility and partition your drive as you see fit. In my case, I created 4 partitions in an MBR setup. I formatted the first one as Mac OS Extended (Journaled) for Snow Leopard, and the other three FAT for Windows and Linux down the road. This will, of course, destroy any data on the partitions you choose to change, and if you resize anything you will probably lose all your data, so think before you click.
Once the disk is partitioned, it's time to install. You've probably done this before, but go ahead and click through until you hit the "Customize" button, and remove everything you can uncheck unless you really want it. Proceed with installation. It will probably say it failed at the end, this is normal. Go ahead and restart, but do not remove either of the USB keys.
After restarting, you'll be back at the small USB stick's Chameleon bootloader screen again. This time, select your hard disk partition to boot from instead of the "Mac OS X Install DVD" option. I would also recommend that you type "-v" before hitting enter on the Apple icon, to enable a verbose boot mode so you can identify any problems should they occur during boot. If all goes well, you should boot up into OSX! There will not be any sound on the intro video, because we haven't actually patched the native file system with the correct kexts yet. Go through the setup process to your liking, and when you're at the desktop, go ahead and download either the NBI or Enabler files, and run them on your OSX partition. Reboot again when the process completes, being sure to remove your USB drives this time around (you might consider ejecting them from OSX before rebooting, they're not needed once you're logged in). Depending on whether you chose Enabler or NBI, your system may skip the Chameleon boot screen and go straight to the boot process. You can circumvent this by hitting F8 right when the cursor is spinning in the top left corner after the Lenovo splash screen, and then you'll be able to enter the "-v" flag if you want. I prefer watching code scroll to watching the Apple spinner anyway.
If all went correctly, you should find yourself booted into OSX.And now you have Snow Leopard on your S10, and you didn't even need to borrow your friend's MacBook to do it!
A few final thoughts on Enabler vs. NetbookInstaller: The Enabler is great and something we S10-ers can call our own, but I did have issues with sound after sleep. I also had an incorrect keyboard layout, and I still haven't found a straightforward tutorial on changing that so that my dang tilde key is working (a must for us command line users). On the other hand, the NetbookInstaller worked quite well for me "out of the box" when I installed it from within OSX after my first boot - including correct keyboard mapping and no "000" bug after waking from sleep. The only exceptions to this were the internal microphone not functioning (known issue) and the system not sleeping when I close the lid (I actually prefer this, I'd rather be able to close the lid and not put the system to sleep, and the Fn+F1 sleep command does work - and it will wake itself when the lid is opened if I sleep manually and then close the lid). So both options have their advantages and disadvantages.
Also, qubit pointed out to me that the Enabler is theoretically ready for the 10.6.3 update whenever that comes out, while NBI is not documented as such. If you're looking for future-proof, it seems the Enabler is on top for now.
I hope this guide is helpful, and please forgive the lack of pretty formatting initially. I'll dress it up and make it more readable as soon as I can get around to it. Good luck!
I know this is more post install, but I think it should be mentioned that vaniii's SL Enabler is all ready for 10.6.3 and Meklort's NB Installer is yet to be modified for 10.6.3 - 
