2 links
Graphic Chemical and Ink Co.
graphicchemical.com
Offers papers, inks, supplies and equipment for etching, lithography, block printing and screen printing. Includes a glossary of terms and a discussion forum.
McClain's Printmaking Supplies
imcclains.com
Specializes in relief materials including tools, wood, linoleum blocks, ink, paper, sharpening stones, gouges, and brushes.