Over 100 artists who work in the collage and/or assemblage mediums have joined a Ning Network website to post and discuss their work. This project was begun by Cecil Touchon in association with the International Museum of Collage, Assemblage and Construction so that members of the museum's email group and community can share their work and ideas in a more multi-media environment. If you are working in these mediums (or simply interested in them), the site is a resource with nearly every kind of work imaginable.
Full disclosure: I have recently started to moderate the site and try to keep it clear of spam. (Where do all these spammers come from?!) The good part is that I'm visiting more often and seeing some really amazing work, a real treat, plus being exposed to the breadth and depth of work these artists are creating.