The National Art Education Association has some of the most amazing professional development at their annual conference. I've been lucky enough to attend my first two years teaching.

NAEA 2010 Conference in Baltimore, MD - Conference Notes
NAEA 2011 Conference in Seattle, WA - I haven't yet added this to the wiki, but check out the Bolivia Arts Blog for my NAEA 2011 Coverage

Online PD Communities
Take a look at Twitter and the Ning Social Networks on the technology resources page for some online options