CPUs 90W and above;
TR U120X or Scythe Ninja 1100 for the Windsor/Agena above 2.6G. (Ninja is cheaper than the competitors without the nickel plating for 1-2C difference. I would have gone with the TR U120X but I preferred the mount on the Ninja. Ninja does hover over the first RAM slot but only a problem for Corsair XMS and OCZ Reaper style Dimms with the radiators.
CPUs below 90W.
Any 4-6 pipe sink like the Katana2 or samurai, themal right 90-120 ultra for all the Brisbanes. Use one of the two sinks above if you plane to go above 2.9G on any of these are just want it cool. I'm using a stock four-pipe sink that came with an Opteron as a cooler on a 5000BE doing 2.95G and is stays below 53C.
Stick with names like Artic cooling, Dynatron(makes sinks for AMD), Scythe, Thermalright, Vantec, Xigmatec and Zalman. There are more names but I'm not sure of the results like from,
Zerotherm, OCZ, ASUS, Tuniq et-al (more than likely good but no experiance with them).