For a single-block solution for the CPU I'd suggest going with this kit over at JabTech for 219.99$:
Pros about that kit:
1) Apogee GT block. Cools dual-cores well and cools quad-core chips VERY well. A lot of guys are using them on quads, so it gives you room for upgrading.
2) MCR220, which is a two 120mm fan radiator. Extra cooling power for quads which heat up a lot more.
3) MCP655, which is a very reliable pump and a good performer. One of the best on the market.
4) 7/16" tubing which won't clutter your case much and will still provide you with good flow. It also seals to the 1/2" barbs tighter than 1/2" tubing, which is a good thing.
In addition to the kit, I'd suggest going with some good steel worm-drive clamps from Petra's, along with some 1/2" DD high flow barbs. The plastic clamps and barbs that come in that kit just don't compare to the safety you'll get w/ some good steel ones. These guys are very reliable; I have bought a lot of stuff from them:
If you don't like the look of the green Hydrx coolant, which is an anti-corrosive, then you can pick up some blue Pentosin which is what I use and has the same effect:
And finally, the last thing you need is a drop or two of biocide. Get this, it's called PTNuke and will keep algae from growing in your tubing:
That's it. Any more questions, let me know. Before you go installing any of this, give a shout to either Buff or myself here on the forums and we'll walk you through the installation process. There are a couple of steps of preventive maintenance like flushing the radiator, leak-checking, etc that are necessary before install. Nothing major, just safeguarding.
Also, keep in mind that load temps are what's most important. Idle temps on these processors with higher clocks tend to climb a bit, but under a full load with high voltage water will dissipate heat a lot better than air or a TEC, and you'll see that. I think my Conroe @ 3.0gHz idles ~30C, but it's been so long since I've had it that low I can't really remember.