I just want to give a big 'thank you' to Slither2008 and moarfish for their contributions to this thread. You have both been a huge help. I'm still new to OS X (kernel extensions were completely alien to me for one thing) but I am far more confident after reading this thread.
That said, I want to point out that IONetworkingFamily.kext may be corrupt in your .zip file. I had to fix the .plist manually for my ethernet controller to work because I would get a kernel panic during boot when I used your kext. Everything else is stable bar one kernel panic upon launching Front Row, and I've yet to get audio working. Those two may be related but, again, I'm still in the starting holes with Snow Leopard (and OSx86 in general).
Anyway, thanks again. You guys are champs.