I just did a podcast over at ESL Teacher Talk about organizing an ESL event.
http://www.eslteachertalk.com/2008/01/p ... sentation/
You can listen to the show directly on-line, download it or subscribe to ESL Teacher Talk via i-Tunes.
The show should give you a little to go on. It basically covers some ideas for picking your presentation content, then talks about some options for what to do once you have your main idea. (Also a few thoughts on what not to do

)