Hey, if you are looking for some good ideas for training equipment you can make yourself, check out this website:
http://www.loop.com/~rockdown. This is Mike Young's homepage. He is a master when it comes to building homemade training equipment. He has a book out in bookstores now that explains how to build several pieces of equipment. However, I just checked and the website appears to be down. Keep trying and see if it comes back up.
If not, try to find a copy of his book, Martial Arts Home Training.