In my case, I called the LGBT hotline at a local LGBT clinic and asked them how I got started on it. (Well, actually I didn't come right out and say it. I just awkwardly said I didn't know what I was doing. but the person on the phone clued in when I got excited she mentioned informed consent). She directed me to call a specific doctor who only dealt with trans issues, and told me that people would know what I wanted just by booking the appointment with her.
I booked the appointment, and somehow managed to get HRT without ever saying the word trans, or even really admitting to it. It was one of the scariest days of my life. But also one of the best.