IMO the ATI 9600XT is the best bang for the buck. It really made the new games like FarCry and Doom 3 just look simply amazing and its really modestly priced for its specs (500mhz\600mhz 128ddr).
I agree that
www.newegg.com seems to have the best prices I have found for building my own computers with reliable shipping and service.
As a computer builder, and player of to many games, I would say stick with the ATI brand, not someone that uses the ATI chipset, but thats just me.
Also, I have a ATI 9000 pro, 9200SE, and a 9600XT and there is a big difference between the last one and the first two.
Enjoy your gaming!