Art Technique & Tutorials
Artshow.com
Very nice site. Tutorials and galleries for painting, drawing, photo/digital, sculpture, printmaking, pastels, and ceramics.
Creativity-Portal.com
A huge directory of everything arts & crafts. Links to supplies and tutorials.
Gurney Journey
Amazing blog from master artist James Gurney, creator of the Dinotopia books.
Pigments and their Chemical and artistic properties
Excellent site!
Portrait-artist.org
An excellent resource for aspiring portrait artists. Tutorials, demonstrations.