if you really want good cooling go phase change. Cost you upwards of 800$
Watercooling is great, but make sure you are well informed and know what you are doing, like maintaining it. You could build a nice loop for around 200$, although i would spend a little bit more.
you would probably be better off investing in a nice heatsink like a tuniq tower or zalman.
heres one tip on WC- DOnt get anything thermaltake or coolermaster. They leak like the titanic.