Ask. There are a lot of vendors at this show that have been doing audio shows for a while. They have expertise and have made connections with many of the other vendors. If you show up to demo your speakers and your amp breaks don't throw in the towel. Start asking the other vendors and somebody will come up with something to get your room running through the weekend. Same with cables or other things. LSAF isn't an "us or them" kind of place, it's a collection of music lovers that are pretty willing to help one another through the weekend. Ask. Somebody will help.
Dinner. There are always a couple of groups that get together on Friday and/or Saturday night to explore some of the local restaurants. Join in! You may not know anyone that well before dinner but everyone at the table is going to be a music lover so you have a lot in common. You'll probably know them pretty well by the end of the meal, too.