Check out the online conference, k12 Online Conference, which will be held October 23 - 27 and October 30 - November 3

Also, a place to get information about various different conferences is David Warlick's Hitchhikr, which uses RSS syndication to aggregate blogs about different conferences.

Another online experience which has been created by Alex Ragone from the Collegiate School is EduBridges.net, which is an elgg site written for teachers to begin to experience social networking sites.