If you've never made or purchased booth weights, you must do so. There are tons of ways to do it. Take a look at artists at the big shows like Main Street Fort Worth, Bayou City in Houston, Art City Austin, and even a few pros here at LAGO FEST this year and last. Here's what I use. Made them myself. SUPER easy and cheap! I hang them from each corner of my tent with a ratchet tie down and then bungee them to the leg at the bottom. Some people even cover them with fabric at the show because they tend to get beat up.
Check out this link. Remember... parks on the water can get windy! http://www.artfairinsiders.com/forum/topics/how-to-make-weights-for-your-tent-for-less-than-30-2
You DON'T want this! Yes, these folks have an EZ-up which are very lightweight and can topple easily. But they DID have ProPanels which should have helped to make the tent heavier. And they did have weights. I can't tell you how many times I've woken up and showed up in the morning on a Sunday - the second day of a show - and seen booths like this. Never fun! GET WEIGHTS!