Erica,
You could maybe ask the doctor for some references? Some women that have successfully transitioned under her care? It's a rare specialty so you may have no other choices except to see her, travel a fair distance (140 mile round trip for me) or move to a city/town that has a bigger selection.
Also, the www has some good sites that cover the subject of choosing a TS specializing therapist, giving a list of good questions to ask, etc. I'm not sure if Susan's has a link but it's worth checking out.
Going to your first therapy session IS a big step. I went to my first last December and found that my anticipated fears were 10× worse than what I experienced. It's a big first step but one of the easier ones, imho. And something has to get the ball rolling! (No pun intended!)
Good luck, hang in there!
helen