that had me shuked too.Wait, what???I've never dealt with this personally in my neighborhood, but odds are this guy is likely on some pretty intensive probation, possibly monitoring, etc., so take some solace in that. You can check your state's specific version of Megan's Law and consult with an attorney in your jurisdiction, but offhand I'm not aware of any direct remedies to you.
My advice would probably be more along the lines of calming down and not becoming this guy: http://en.wikipedia.org/wiki/Stephen_Marshall_(murderer)
While in Cape Breton, he met Greg McNeil, and once compared a small girl to a pebble.