How bout i bring the Hardware forum to you since i am an IT person....
CPU: Q6600 $270
RAM:pqi (2 x 1GB) DDR2 800 $38
MOBO:GIGABYTE GA-P35-DS3L $89.99
HD:Seagate Barracuda 7200.10 ST3250410AS 250GB $70
Optical:SAMSUNG SH-S203B $30
Case:CoolerMaster Centurion 5 $35
Vid Card:MSI 8800GTS (G92) 512MB $309 OR eVGA 8800GT 512MB $249
PSU:CORSAIR CMPSU-550VX $99
If you don't already have an OS available:
Vista Home Premium $109
XP Home $90
Now I'd be surprised if you didn't already have an OS, but depending on the config you can either rock a G92 GTS or a GT. It all works out to +-$1000, and if you're adventurous and go for the MIRs you can save more. You can save more by going with a higher clocked dual core (quad, apart from SupCom, really isn't utilized in gaming, but it's nice to have the extra two), so you have some flexibility as far as options go. You'll also notice that while I didn't necessarily go for the highest end parts, I certainly didn't cheap out. Each part is good for its purpose; even the really cheap RAM is spec'd well above what that Q6600 needs, so you have quite some overclocking headroom (which the P35 should do well with).
and I know that this is technically derailing the thread, but I'd just like to point out that this was a train wreck in waiting. I just put the penny on the track
EDIT: I also want to mention that all of the prices above are not taking in to account possible MIRs, and more importantly aren't necessarily the lowest prices. I really didn't bother to look, considering I'm doing this at work (shhhh)
EDIT2: I also forgot that they're still selling those 640mb GTS (G80s)...I haven't checked the benches but it should slot in nicely between the GT and G92 GTS