In the old days--back in the mid-1970s, when I was a teenage wannabe--books about blues harmonica were pretty much the whole deal.
There wasn't any internet filled with YouTube instructional videos. There weren't any digitized, downloadable videos and tabs of the sort peddled elsewhere on this website. There weren't any lessons in CD or cassette form.
If you didn't know an actual harmonica-playing bluesman who could teach you in person, the only sources of useful information were whatever records were available at your local record shop and whatever instructional books you could scrounge up at your local music store.
The world has changed a great deal since then. Everything has speeded way up. The dearth of information has been replaced by a glut. Prospective blues harmonica players are drowning in guidance, thanks to the web. (Not all of it is helpful or well-informed guidance.) But blues harmonica instructional books are still being written, and some of them, old-school as their delivery system may seem, are worth having.
That's what you'll find on this page: a selection of printed blues harp instructional materials that both beginners and more advanced players will find helpful. Every single author below is a top pro: not just a skilled player but a gifted teacher. Many of the authors are friends and acquaintances of mine; I can personally vouch for their gifts. If you purchase several of these books, you'll usefully supplement the instructional videos and tabs available elsewhere on this website.
When you've had your fill of instructional books, you might want to broaden your investgation with one or more of the following: