I just recently joined the International Street Painting Society!
They are "...a totally new organization, which will focus on connecting street painters worldwide. There are other local or national organizations, both for chalk artists and general artists, but this non profit 501(3)(c) group will focus on street artists (which can include chalk & paint, traditional and 3D). We hope to elevate awareness and educate the public, on an international scale, about street painting"
Check out there website: http://www.internationalstreetpaintingsociety.com/