Pro Resources

General
Organizations
Graphic Artists Guild (GAG) - http://www.graphicartistsguild.org/

By Specialty
Animation
Organizations
Animation World Network (AWN) - http://www.awn.com/

Caricature
Organizations
International Society of Caricature Artists (ISCA) - http://www.caricature.org/isca.php

Comics/Cartooning
Organizations
Comic Artists Guild (CAG) - http://comicartguild.org/
National Cartoonists Society (NCS) - http://www.reuben.org/news/
Association of American Editorial Cartoonists (AACE) - http://editorialcartoonists.com/

Computer Graphics and IT
Organizations
ACM SIGGRAPH  -http://www.siggraph.org/

Illustration
Organizations
Illustrators Partnership of America (IPA) - http://www.illustratorspartnership.org/index.php
Illustrators Society of Illustrators (SI) - http://www.societyillustrators.org/