I'm not big into reading, but there are a few books I enjoy and I read quite alot of manga. Here are some of my favorites.

It's hard to find the official sites of Japanese artists so I couldn't get any direct sources. Click the images for the site I found them on.

Uzumaki Uzumaki(Spiral) by Junji Ito. Probably my favorite manga, Uzumaki is a horror story about a town under the curse of the spiral.
Berserk Berserk by Kentaro Miura. Berserk is especially interesting to me. Berserk is a Japanese take on Western fantasy, it's cool to see the different interpretation.
Dr.Slump Dr. Slump by Akira Toriyama. A little out of place compared to my other favorites, Akira Toriyama is a great artist and his style sense of humour translates well to English. He's also the artist and author of another of my favorite series, Dragon Ball Z.