rbernard, the big question when it comes to stands is do you want it to be something very durable that can withstand a hit from what ever you are shooting at it, or do you want something cheap that you expect to break after a few hits of the stand and is cheap or easy to replace.
For the first option, its going to be hard to make it very portable since it will most likely be made of heavy steel. However, if you go the second route for more or less disposable stand, you get many more options. They range from nailing together some 2x4s and drilling holes in the base so you can stake it down, which will get very chewed up by splatter, to buying some threaded steel piping and rebar. You make a big upside down U out of the piping, and drive the rebar into the ground leaving a little over a foot stick out. Slip the pipe over the rebar and hang the target from the top of the upside down U. The steel piping shouldn't be affected by the splatter, can take a few direct hits, and can be carried by two people with out a problem. You can also do more or less the same thing with PVC if you are shooting smaller rounds, but it will get chewed up by splatter eventually and you might cut yourself on embedded splatter. Pulling the rebar out of the ground when you are done is a bit of a hassle though.