Has anyone worked up a history of the LPIN Gathering? That might provide a good roadmap to follow for developing this. If memory serves (I was only able to attend the 2006 event), didn't someone just throw a barbecue, initially? That might be an easier way to start than something as formal as a banquet, besides, if you start to run out of something, you can always send somebody on a grocery run.
While I'm not terribly keen on Las Vegas, I'd be willing to give Pahrump a try, work schedule and logistics permitting.