Specs:
MoBo: GA EP45-DS3P
Graohics: GeForce 9800 GTX+
CPU: Intel Core 2 Duo 3.16ghz

I went with the easy route and tried this Tutorial but now when I try and boot up I can get to the Apple logo loading and sometimes to the installer(Chose language->next to install...) If I get to the installer it crashes pretty quickly but I can still open disk utilities although that then crashes a few seconds later. If it doesn't make it to the installer screen while the apple logo has the loading wheel underneath it it will Kernel Panic.

I have to assume that because that tutorial is for the EP45-UD3P that it doesn't install a few necessary kexts.
The problem is I am unable to find the correct kext for the motherboard. And I don't know how to add them to the current ones.

EDIT: Wrong section, can a Mod move this to the OSx86 installation, snow leopard section.

I used the same method and it worked flawlessly so far except I have done a few other things as well. Did you set up Bios alright? I booted off the thumb drive and got to the install screen. I opened disk utility reformated drive and used the proper partitioning. Installed after install and chose to boot off of HD at boot screen. Booted into Mac OS and installed the custom bootloaded that allows me to boot without thumb in. It has worked well so far except I have no sound and flash does not play properly in Safari and Firefox?? I have the G41M-ES2L Board.

I did it using fasls dstdt patcher, drhurts chameleon installer/package, one of these 132 for SL and a restored SL image from my old Leo install to a fresh Guid formatted USB hardrive. Don´t install printerdrivers first time might give you KPs or install wount finnish. First reboot you ofcourse need the 132 disc but then run the dsdt patcher and put the dsdt.aml you get (it´s a one klick operation) inside the chameleoninstaller/package (rightklick show package content) Contents/Resources/Extra along with a modified com.apple.boot.plist and platformUUID.kext with your personal harddrive UUID and the rest of the kext you need in extensions. Run the chameleoninstaller/package reboot and your good to go, hopefully anyway. Pretty close to the good old way so no need for no USB pendrive or anything.

The kexts I´m using is the
fakesmc.kext
IOAHCIBlockStorage.kext
OpenHaltRestart.kext
PlatformUUID.kext
and a NVinject.kext I´ve edited myself to work with my two noname 7300gs 512mb Pcie videocards