I think equine massage therapy would be a great thing to learn, especially because it does great wonders for horses. The new mare I got is pretty stubborn and not too keen on listening. I couldn't even catch her in the pasture without going on a wild goose chase. I just used a few techniques of massaging that I learned simply by searching the web and it only took a few times before she followed me around the pasture no matter where I went. She'll even hold still for a good hour without moving.
I'm not certified or anything, so I know nothing much about the people who could teach you. Maybe you could try and find other equine massage therapists to see what they would chose, or what they did.
Good luck in your endevour. ^^