You thought I'd forgotten about my "Favorite Books" series didn't you? Ha! You only wish...
Here are some books on comics and storytelling. Even if you're NOT a comic book artist (or wanting to be one) these should be very valuable sources of inspiration and info about that most vital of component of the illustrator's craft - how to tell a story visually. Whether with a whole book of panels or a single drawing, we need to get the idea across as much punch and entertainment as possible. These books have a lot of the nutritious information you need, plus they're pretty good reads as well.
Comics and Sequential Art by Will Eisner
Will Eisner, the master of comic book storytelling gives us the basic building blocks and principles of comics. It had never been put in print before, and this book still holds up as perhaps the main pillar of graphic storytelling theory. If you are at all serious about telling stories visually, you should give this one a try. (And if you haven't read his Spirit comics you really should - especially the five years or so after WWII. Those are some of the greatest comics every made!)
Graphic Storytelling & Visual Narrative
Where Comics and Sequential Art gave us a framework for graphic storytelling theory, this book goes more into the practical techniques of effective storytelling, with lots of examples from both Eisner's work and that of other comics masters along the way. Eisner shares his genius in a clear and entertaining manner as always - you need to read this book if you haven't already!
Understanding Comics by Scott McCloud
Scott McCloud's amazing book covers not just comics, but really his philosophy on art and creativity. This is a must-have book for visual storytellers of all types. Clear yet deep, funny in places and always useful.