this is a textbook for lighting design I know a LD uses for his college courses. Are there any local theatres near you, you can contact and ask if they have apprenticeships or internships or that you can just go and observe how they operate? As for school, do you cue the show during tech? That's a great way to learn about design is to watch the designer cue the show and program the board.
This is the text we used in my lighting design curriculum in college. It's been a while since I read it, but I recall liking it.