The fourth annual Electro-Music Festival/Conference (EM08) will be at Kingsport's Renaissance Center Aug. 14-16 in Kingsport, Tennessee. For the past three years this event has been in Philadelphia as well as The Netherlands. This year the organizers wanted to bring it to the Southeast.
There will be a call for performance participation on the Electro-Music.com website. http://electro-music.com/
If you would like to perform, demo, instruct, etc., keep an eye for the announcement. Check the forum as well for announcements and participation fees. If you just want to hear the performances, or walk around, the general public will be able to buy passes.
Electro-Music involves more than just music. It has a very active do-it-yourself electronic synth building community as well as circuit benders. There is an active MAX/MSP software developer community as well as Clavia, DJs, etc.
Here's a page of photo albums of many of their events.http://electro-music.com/forum/gallery2.php