docs associated with medical schools tend to be more current on recent developments. Try searching through the website of a nearby medical school and looking for their particular area of interest within the specialty.
USA Today does something like that with "America's Top Doctors" when they do the best hospitals in each specialty every year. It seems to me that it's like the Who's Who of XXX that goes around, except it's for the health care community. Glorified advertising I guess.
Definitely the best way to find the best doctors is word of mouth between docs. If you don't know any docs, start at the academic centers and try to find out from them who the leaders in the given specialty are.