The 10’ers is a livejournal community of young adult and middle grade authors whose books are debuting in 2010. Lots of great stuff on the site. I recently joined, and you can find my introductory bio here: http://community.livejournal.com/10_ers/322902.html. I might cross post there from time to time, if the subject matter also seems appropriate for that site.
There’s over 80 other authors listed on the site. Check them out!