I'm from Nashville and am on TRT. My doctor is through Vanderbilt (James Macdonald in Williamson County) but really he's not much help other than tests and the Testosterone rx. He can get you started though and then you may need to take some of it into your own hands (things like AI and HCG). Todd Doran is also at Vanderbilt but, in my experience, he's kind of a flake.
There are a bunch anti-aging/men's health clinics popping up (there's a billboard for one on 65 N). I looked and this guy isn't covered on my insurance so he's probably one of those guys who charges for the appointments and "treatment" (which is you coming in and getting a shot). The last one I saw was like $145/month and you paid for the year in advance.