Well, if you're just going to cool the cpu, you need a waterblock, radiator, pump, reservoir, and the appropriate tubing/clamps.
Check out frozencpu.com and dangerden.com for supplies. I recommend the D5 pump, maybe a single 120mm radiator with fans pushing and pulling. I also recomment going with 1/2'' diameter tubing, but if you're only doing the cpu, you can go with 3/8'' tubing if you like.
The swiftech apogee is still one of the best universal blocks out there. Good luck.
Edit: For price, I don't think it should be more than $200 USD.
Check out frozencpu.com and dangerden.com for supplies. I recommend the D5 pump, maybe a single 120mm radiator with fans pushing and pulling. I also recomment going with 1/2'' diameter tubing, but if you're only doing the cpu, you can go with 3/8'' tubing if you like.
The swiftech apogee is still one of the best universal blocks out there. Good luck.

Edit: For price, I don't think it should be more than $200 USD.