before scales and stuff like that you need to know about time signatures and tempos and stuff like that. You should definately be playing with a meteronome. These ideas are incorporated in reading music. Before learning about scales it would be a good idea to learn about how chords work first to have a solid foundation for the more advanced concepts. You can probabily find a book that teachs about reading music and chords (harmony) at most book stores. If your going to teach yourself theory it might be a good idea to get a cheap key board to learn it on.