Art Books
The list of books I have provided below are worth their weight in gold. I have broken them down into Beginner, Intermediate, and Advanced under the two sections of DRAWING and PAINTING. These should keep one busy for a few years.
DRAWING
Beginner - Intermediate
How to Draw What You See by Rudy De Reyna
Famous Artists Course in Commercial Art, Illustration
Intermediate - Advanced
Figure Drawing for All It's Worth by Andrew Loomis
Drawing the Head and Hands: by Andrew Loomis
Drawing Dynamic Hands by Burne Hogarth
Successful Drawing by Andrew Loomis
Advanced
Drawing Manual: by Glen Vilppu
Figure Drawing: Design & Invention by Michael Hampton
Creative Illustration by Andrew Loomis
How to Draw Portraits in Charcoal by Nathan Fowkes
PAINTING
Beginner - Intermediate
Acrylic Painting by Rudy de Reyna & Wendon Blake
Painting in Opaque Watercolor by Rudy de Reyna
Intermediate - Advanced
Fantasy Workshop by Boris Vallejo & Julie Bell
Mastering the Craft of Painting by Angelo John Grado
Advanced
How to Paint Like the Old Masters by Joseph Sheppard
The Student’s Guide to Painting by Jack Faragasso