The Vantec Aeroflow for the P4 should be pretty good, and it uses the standard retention bracket, which means a no-hassle install. I haven't used the P4 version, but the AMD version is pretty darn quiet, and it keeps even the old 1700 Palomino it's on very cool compared to the old swiftech cooler that was on it.
Other than that, overclockers.com has a pretty up-to-date heatsink rankings page here:
http://www.overclockers.com/articles373/
That page has links to their reviews, as well, so you can see what kind of mounting mechanisms they use, and how easy they were to set up.