II am a self-taught artist. This means that I spend most of my time thinking, doing and researching art related things. I recently read a few artists' biographies. There is a lot to be learned about art they created by reading about their lives, personal choices and paths they traveled.
Edmonton Public Library is a good place to get good books on art - I usually place a hold on a book and pick it up at a library closest to my home. Right now I am reading Mad Enchantment - a book about Monet. It is quite an interesting read, as it is clear that things really do stay the same throughout the history and artists have similar anxieties and hurdles even in different times. Not to mention ego wars, big personalities, solitude etc.
My favourite still are Van Gogh's letters, which I love to read over, especially when I need motivation to continue with my art endeavours.