Charlotte Riley-Webb
Illustrations of the silk-screen printmaking process
www.charlotterileywebb.com

Judy Martin
Encyclopedia of Printmaking Techniques
The book at Amazon.com

History of Printmaking
http://char.txa.cornell.edu/

What is an Original Print
http://www.studio1617.com/prints.htm

Handmade prints
Washington Printmakers Gallery

Art of the Print
http://www.artoftheprint.com

Handmade paper, watercolor, color theory
http://www.handprint.com/HP/WCL/water.html

Caring for works of Art on Paper
http://www.worldprintmakers.com