Because stained glass comes in a variety of sizes and shapes it is difficult to find a creative way to juggle everything. Stained glass is heavy and needs support. When we set up a craft show we typically hang most of the panels from our tent. You will have to have a tent to vend at most craft shows outdoors. Usually craft shows assign each person a 10x10 foot space which is the exact size of the tent space. Even if it is not required I would suggest getting one. As soon as the first drop of rain starts to fall you will be glad you have one. We have a pretty heavy duty tent (not the kind you get from Walmart). Using one with steel bars and some kind of weighting system works best. Weights are essential outdoors.
I am attaching some photos of how we have hung work in the past. You will need to use a chain that can be opened with needle nose pliers. This is how you will secure your work to the tent. Zip ties work even better. Lowe's sells them in the electrical dept. These work great for hanging most anything. They will hold very heavy panels with ease. To take them down all you have to do is cut it with scissors or a razor knife. (Watch the fingers! My boyfriend had a small incident recently doing this.)
You may also check out the hook section at your local Ace hardware store. They have a variety of them in all sizes. You might be able to rig something up for easy set-up and release.
As for using panels or stands. I do not think this is a good solution. The weight and instability of the panels is most likely going to cause it to fall, if you get just the right gust of wind, someone bumping into it, or a slight earth tremor that is.
A tip from me to you - You should never sell at an outdoor show during a storm or heavy winds. You will most likely have a disaster. We attempted to do this recently thinking that we could get through it and ..it was a nightmare. Wind is NOT a friend to stained glass. Rain is not as bad but you end up cleaning everything in the end.
Things to bring that will make the day much easier:
Extra wire, scissors, two pairs of pliers, lots of small chain, duct tape and packing tape, cardboard and bubble wrap for wrapping things, extra price tags, a table, cash change in small bills, business cards, zip ties, a step stool, and razor knife.