Anime South runs from the 18th to the 20th in Destin, FL. Besides the usual Cosplay, Panels, Viewing Rooms, and Maid Cafe, they have some unusual events, like Anime Speed Dating and the Anime Tractor Pull. Musical guest Eyeshine seems to be touring the Anime and Sci-Fi Con circuit this winter, so they may be playing near you sometime soon.
Also this weekend, Tsunami 16 2009 happens in Merida, Yucatan Mexico. Unfortunately the homepage, while one of the most visually stunning images I have seen for an Anime con, is just that: a JPG image. A bit difficult to click on anything and get more information.