My advice would be to not buy a book. You already have access to the biggest "book" there is,
, along with more code samples than you could ever look at. Search for code to do the things you want, like adding music playing functionality. Believe me, someone has already coded what you want to do. Then borrow that code and add it into your program framework. After studying enough examples, you'll eventually be able to program things on your own. Add a nice interface to look just the way you want, and there you have it.