Chemicals: I really don't know the first developer I started using. I started developing at home when I needed better quality than the lab could give me. I know that I used D-76, HC-110, Xtol, Tmax developer, and a bunch of others. Then I decided to stick with Xtol and be done with it.
Training: Self-taught. I bought a book, chemicals, bottles, and Patterson stuff, and dove in. The first book I bought was by Bernhard Seuss, and the AA series was next. I've never taken a class.
Materials: Film emulsions have come and gone. I liked Ilford Universal 400 on half-frame, and Techpan on medium and large format.
Full Circle: Still using Xtol. Still photographing with the same cameras and lenses. Never left them, never needed to change. As long as it can be repaired, I'll still use it. As for consumables, the major films are still being made, no big deal. Ilford makes great paper. I really don't bemoan (not too badly, anyways) the absence of any material ... OK, so I miss Kodak E6 and HIE/HIR. Besides that, I'm fine with what's available now.