Fragswapper is awesome! Takes a minute to get used to but after that it does all the work for you. Also eliminates the what are you bringing threads on multiple sites which makes it tough to keep track. I've never hear of using incentives but all presales are done there...think All-Ohio Swaps - sometimes 20 pages of NOTHING but listings.

Another idea would be a diagram of the layout where people who have table could write their name...that way if you're looking for someone you know where to head. Only 1 swap has done this, but man did it help!