First of all, are you looking for extreme cooling while overclocking or just a silent cooling solution? I've got tons of waterblocks sitting around - I can just send you one. (Call it a trade for the really cool CNCZone hat that I'm wearing
)
Here's what you need to piece together a good watercooling system: pump, waterblock(s), tubing, heatercore (AKA radiator), hose clamps, and a fan to blow over your heatercore.
For the radiator just pick up a small heatercore at autozone. That should cost you about $20-$30. You can solder/jb-weld hose barbs onto it pretty easily. If you need help choosing the size, let me know. The Chevette HC is a popular size, to get you started.
Pumps - there's a lot of different choices here, but some top recommended ones are the Danner Mag 3, Eheim 1046, 1048, or 1250, Iwaki (almost any will do, but they're pricey!) and sometimes the Hydor L30 (I've heard of some quality concerns).
As you may know, I'm associated with a watercooling website, so I won't advertise their wares. However, here's 2 other great companies to order from.
www.dangerden.com (The RBX with a brass top is a great block.)
www.dtekcustoms.com
Fans - get a 120mm fan if it will fit. You'll get more airflow at a lower noise level. Panaflo seems to be the popular choice here.
Tubing - Don't waste your money on Tygon. It's very expensive, and the same thing can be accomplished with PVC. I prefer ClearFlex or mastercleer (
www.mcmaster.com). Get 1/8" wall thickness, not 1/16". It won't collapse nearly as easily.
Hose clamps are just common sense goodness. Don't skimp here.
Also, some of the very inexpensive WaterCooling kits will actually perform worse than a good air cooled heatsink. (The one linked is not a great performer.) Just do some looking around before you buy, and ask any questions you may have.