I'm not sure about your question, are you actually wanting a mannequin or not?
If you Just don't want to spend the money on a mannequin you should keep reading.
If you just want a stand, yeah just like Alex said, get some PVC and fit it together.
I summed up what i did really quickly below, but there is also a really detailed picture aided tutorial on the site that will help you build your own mannequin from old clothes and duct tape. Our methods differ only slightly. His post should have been made into a sticky in my opinion, this method is really amazing and cheap.
Bamabat's post:
http://www.405th.com/showthread.php/19547-Duct-Tape-Dummy-Tutorial?highlight=build+mannequin
Materials:
tape
clothes
stuffing material
scissors (medical ones are safer)
Cost for me:
Tape ~ $20
Stuffing ~ $20
I had clothes & nice Scissors
PVC piping ~ $15-$25
so like $60 bucks total.
Step 1: Get an old shirt (long sleeves). Sweaters work nice too b/c they can stretch a bit and get all the nooks and crannies... You'll see what i mean.
Step 2: Duct Tape.... lots of it... Depending on your size and how much of your body you want to make into a mannequin you'll need like 3-4 rolls.
Step 3: Starting with X's across the chest have a friend Tape the shirt to you. You want long continuous pieces, The strength of the mannequin is gonna depend on the quality of the taping job. The X's work as a structural frame, now just wrap your body in tape, head to toe or whatever. You want the tape tight, tighter the better, just be warned about the pressure on your chest, it will be a little hard to breathe if you go too tight. This is the meat of the project so take your time and get it right. You want several layers of duct tape over every part of what will become your mannequin, Again strength, strength, strength. Later on you will be stuffing this thing in order for it to fill out to resemble your body, pressure on a weak spot will cause tearing.
Step 4: cut it off with scissors (carefully) and try to cut as little as possible for you to squeeze out of it. You want as much of the original structural integrity as possible, because anyplace you cut is going to have to be re-taped to complete the mannequin. The bigger the cuts the harder it is to get the mannequin back to the perfect size of you.
Step 5: Re-Taping/Stuffing. This is the hardest part of the project, so the more time you spend on this, the better it will come out.
STUFFING MATERIALS: you can use whatever you want.. I bought the cheap polyester pillow stuffing from Michaels. I think i must have bought over half their stock in it too... I got some wierd looks b/c i came back 3 times in 1 day for a full cart load of the stuff. It was on sale at a buck a bag, so its pretty cheap.
RE-TAPING: I wanted my mannequin to have a neck so i taped my neck (weird feeling) so to start i taped shut the neck and started stuffing the shoulders and collar area. Tape the cut areas exactly back together with small strips, almost like stitches. Later once the area is stuffed you want to go back over it with tape again in the same wrapping method you used originally to make it very strong. Don't skip this... Just leaving the temp tape job will cause a weak spot that is sure to split open eventually.
Step 6: Stand. PVC is the best thing to use for the price and load bearing capabilities. Build a " T " to fit inside your shoulders and an " H " for the base of the stand. You'll want to start incorporating the stand while stuffing it... Like as soon as you have the shoulders and neck area done. The tighter the pack around the frame inside the dummy the more sturdy your mannequin will be on a stand. That's pretty much it though. Just tape the bottom closed using another piece of material for a base... Cut up shirt works. Make sure to make a hole for the stand and you're done.
If you have any questions I'll be glad to clarify for you w/ pics if you like. Make sure to read the other Tut on this too.