Sablebrush, I've made some magnetic pipe racks and stands. At the end of this post I'll post links to the threads.
My personal experience is that to attain any serious level of stability you have to use one 20 pound magnet beneath the pipe and one 6 to 10 pound magnet inside the pipe. These are neodymium magnets, not regular magnets. Regular ferrite magnets would be very big in these ratings.
You can get them on ebay or Amazon. Just search for neodymium magnets and look for the right rating and size.
PM me if you need any additional details. If I can, I will gladly help you design you rack/stand.
Cheers and good luck with your project,
J
http://pipesmagazine.com/forums/topic/new-magnetic-pipe-racks-pics-2
http://pipesmagazine.com/forums/topic/ultimate-minimalistic-pipe-rack