So, i'm looking to build a desktop soon but ive enver actualy dealt much with computer hardware

can someone suggest where and how much? i think those small cases are cheaper or something? barebox or something...

I think i want at least..

-AMD 64bit 3.0 ghz processor
-1g DDR ram
-256mb Vid card.

i'm really not to picky on anything else, from what ive gathered.... i can buy one of those small square boxes bare and get all the parts is that right? suggestions would be great.

oh, and this wuold pretty much be for gaiming only.