I’m interested in physician salary surveys. I am a Medical Group Management Association (MGMA) member and have their surveys. I’m just wondering whether there are any others worth looking at?

The MGMA is the standard, but the AMGA and some others have them as well. 

Recruiter Merritt Hawkins posts a nice summary from 

 on its Web site, and you can see their sources if you want more information. You should also double check whether your state medical society or specialty society has data.