The first is a book by a comic icon - Stan Lee. The book is Stan Lee's How to Draw Comics. The book starts with the basics of what materials are necessary and what materials are helpful. Then it moves to drawing instruction; faces, head shapes, bodies, backgrounds. Everything you ever wondered about drawing comics is here. The book even talks about naming your characters. So, if you want to learn from one of the best, this may be the book for you.
The second book is The Complete Guide to Figure Drawing for Comics and Graphic Novels by Daniel Cooney. This book helps the artist learn how to move a drawing from a photo, a model, or the imagination to a character on paper.
So, if you ever thought you'd like to draw comics, maybe one of these books will help you to get started.