Graphic Design Books/Resources

I'm looking to improve my design skills and as I don't have the time/money to pursue another degree, I would like suggestions on books or other resources that I could learn from.

Also, if you were to recommend one or two design classes that would be the most beneficial, what would they be (art history, beginning design, etc.).

I do know all the appropriate software (Photoshop, Illustrator, Quark, Flash, Dreamweaver, GoLive, etc.), I'm just looking for suggestions on learning design.

Thanks everyone,
-monster.