Well I dont know your budget but...
Here's what I have...
Nvidia 8800 GTS 320 mb OC edition
Intel Duo E6750 2.66 Ghz
Kingston 2Gb 800 Mhz DDR Hyper X
MSI P35 NEO - F motherboard
I have this system for 8 9 months and the game is at 1028 x 1024 resolution with all the details are full, AA with HDR (since you can manually force it) I have a really low res cause I have a 17" CRT Samsung Syncmaster... I dont really like the LCD monitors...
I got the whole system for like 1200 USD but it should be like 1000 USD now since it has been 8 months... the prices are lower now... But for this baby to work, you will need a 600W power source too

the 8800 is killing me