(in no particular order...)
Helpful books to have in your library:
"Carlson's Guide to Landscape Painting"
by John Carlson
This is the plein air painter's bible. If you paint outside, buy it.
"Fill Your Paintings with Light and Color"
by Kevin MacPherson
The other plein air painters' bible. Just buy it too.
"Composition of Outdoor Painting"
by Edgar Payne
A difficult to read how-to book due to a somewhat wordy writing style, but worth the attempt nonetheless. Many buy the book just to have Payne's thumbnails that explain various compositional ideas. But remember, despite what Payne may try to tell you, there isn't any magic composition that will work every time.
"Alla Prima, Everything I Know About Painting"
by Richard Schmid
One of the best living observational painters there is. This is not a how-to-paint book but rather a how-to-see book, which is far more important. If you can have only one book in your art library, this should be the one.
"Hawthorne on Painting"
Mrs. Charles W. Hawthorne
There are some interesting traditional techniques covered in this book. But some of it is a bit outdated by contemporary conservation science. But it is an interesting read anyway.
by Mark Christopher Weber
Excellent resource for different ways to lay in the paint. Weber's book offers practical advice on what kind of brush to use, how to hold it, how to load it, and how to touch the surface. Will help you maintain a variety of marks, which will always adds interest to the surface of your work.
"The Art Spirit"
by Robert Henri
A classic. No, the classic. The book to thumb through whenever you start to feel a bit discouraged.
"Alla Prima: A Contemporary Guide to Traditional Painting"
A pretty good how-to book that introduces most of the issues a novice painter will encounter when starting out, but I'm a bit at a loss as to why the author considers a two or ore sessions to qualify as alla prima.
"Changing Images of Pictorial Space:
A History of Spatial Illusion in Painting"
by William Dunning
A deeply profound and enjoyable art history book that explains the different ways the great painters of their time depicted space and volume – from pre-Renaissance to Post-Modernism. Don't let the title put you off. It's a must read if you want to know your stuff, and the author (now deceased) was once a noted sculptor and painter himself. I actually picked up a lot of painting techniques from this book, even though it is largely an art history survey and not a how-to manual. It's one thing to say Leonardo da Vinci, Caravaggio, and Rubens were different from each other. It's another to actually understand how. And why.
"The Judgment of Paris:
"The Judgment of Paris:
The Revolutionary Decade that Gave the World Impressionism"
by Ross King
Another interesting read about the conflict between the French Salon and the French Impressionists. It offers a lot of the economical and political context that surrounded both camps. Gives you a good feel for the crazy passions of the period.
"The Principles of Harmony and Contrast of Colors"
by M.E. Chevreul
(Translated from the French in 1894) Chevreul is the man who codified the Hue/Value/Chroma breakdown of color, and many of the effects colors have upon each other when placed in close proximity. Chevreul's scientific approach to color theory launched French Impressionism, and all other painting movements that followed. More contemporary theorists merely restate Chevreul's original thesis. Itten, Albers, and Munsell repeat what Chevreul has already laid out, so if you've read any of them then you will understand this book.
And speaking of Itten...
"The Art of Color:
The Subjective Experience and Objective Rationale of Color"
by Johannes Itten
This is Itten's larger book on color and it will fill up your lap. I recommend it over his abbreviated book "The Elements of Color" because it not only does it illustrate the Laws of Simultaneous Contrast, it presents examples of how they work in European masterworks. It is one thing to understand color theory, and another thing to see it put in practice. However, I offer one caveat: since most copies currently in circulation have been printed using a standard four-color printing process, some of the color effects discussed are diminished. If you ever come across one of Itten's early hand silk-screened editions at a garage sale, buy it. It's worth thousands...
Art resources for paint, panels, gear 'n' stuff: