Ah, drawing is something I'm full of advice on, but sadly I don't think much of it applies in terms of introduction. Those "How to draw XYZ" books are actually really helpful so long as you get a good one. I learned a lot on muscle structure and organic tissue from a simple How to Draw Dragons title you could probably find at any bookstore. Just poke around in a local bookstore until you find something that interests you and that you would have fun drawing, the most important thing is that you continue practising, and if you can do a drawing a day from a book, source material that interests you is very helpful.