If you dont want to do the classes, you can get videos that show you what you can do with one flash and some bounce boards and stuff like that. I dont remember the guys name though that ive seen videos of.
My lighting teacher promots the kiss theory. keep it simple stupid. The less lights you have, the less work you have to do. The more lights you have, the more shadows you have to try to eliminate since there should only be one set of shadows for a natural looking portrait.
I just did my portrait assignment, hopefully itll turn out well. I only used a hand held flash off camera for the main source of light. I was planning on using some bristol board to bounce some light behind the subject for rim lighting to seperate the subject from the background but I didnt have anyone to hold it in place.