www.artfairinsiders.com is a great site created, ran by, and for artists to share information with each other.
The site is broken into several links for sharing information on art shows, photos, artist's classifieds, and just general sharing with each other. I discovered the site a few months back, and it's already becoming an absolute must in my daily art life. I search for information on art shows and get real comments for real artists. Additionally, I've met a number of great people through the site that I've met at art shows.
Visit it soon.