Water cooling is nice if you don't like your room sounding like GM's wind tunnel.
Your best best for the easy way, is to get a Koolance that already have the work done.
Thermaltake also has a nice add on unit for people who are attached to their case.
If you want to stay aircooled however, check out Thermaltake.
They've got a nice heat pipe cooler for your vid card and a monster heat pipe for the CPU. Their cases are really well designed for airflow too. I love my XaserV Damier.
I was running watercooling about 3-4 years ago. It's nice for the sound dampening and for the cooling affect. It is, however, very costly.