I read a book called "Starseeker" by Tim Bowler. It was a fictional book, but I think a little too old for a 12 to 13 year old though. It's about a boy who's the son of a concert pianist who dies when the boy is 15. He's angry and falls in with a bad crowd, stuff happens etc etc.... but there is music intertwined the whole way through, like a recurring theme almost. I enjoyed reading it not only because it's a good story but because it mentions titles of music that exists it made me think of the music to go with the book, if that makes sense.
Sorry if I wasn't entirely helpful, but I just wanted to get a mention in for a book I can thoroughly recommend to anyone who likes reading and music!