Here are 5 really good books for you if you are a serious harmonica player and want to expand your repertoire and practice your techniques. You get:

Graded Studies and Solos for Harmonica, book I (for diatonic) and book II (chromatic), by G. Romani

Amazing Grace and Other Gospel Sounds for Harmonica, by Ken Arnold

Quick Success Harmonica Course in 10 Lessons by Jack Hammond and James Sexton

and Pop Standards for Diatonic and Chord Harmonicas by Bob Bauer.

All are in like new condition except for Pop Standards which is really ver nice but a little bit shelf worn as it is an older book.