The following is a list of recomended books for karate study.
1. Best Karate Series by M.Nakayama JKA syllabus on Kata and Bunkai applications, 10 books in total. (as the title sugest it is the best)
2. Dynamic Karate by N.Nakayama.
3. Shotokan Karate K.Enoeda (series of books) 10-6th kyu 5th kyu to black belt.
4. The Karate dictionary Schlatt – karate terminology explained
5. The beginners guide to Shotokan Karate John Van Weenen
6. Advanced Shotokan Karate John Van Weenen.
7. Magazines – Shotokan Karate Magazine or SKM comes out regularly and has some interesting articles.
There are more books available but these are the most basic ones to start you off on the road to your Karate studies.
For the more advanced students there are books by master Gigin Funakoshi, his life and his most famous publications: the twenty guiding principles of karate, karate-do my way of life, karate do Nyumon, karate do Kyohan (this started shotokan karate off globally).
Also very good read Sensei Hirokazu Kanasawa Black Belt Karate, Fighting techniques, Shotokan katas etc…
We hope this will help you in your karate studies.