Length of trot poles and canter poles?

I am curious about the length you should set up trot poles, which I've heard will help to teach a horse to trot consistently and also to pick up his feet.
I would like to do this with my 16.1TB, but am not sure what length to space the poles for trotting, cantering, and gymnastics.
Any ideas?
Thanks!!

For trot poles, I was taught to put a pole down, then take 2 normal steps and put the next pole down (that make sit approx. 6' apart). For a short legged horse or pony, 1 normal steps. You just have to play around with the spacing until you figure out what works best for your horse.

Here is a good document giving approximate distances:
http://www.grandprixdesign.com/image...ic_Jumping.doc

Some articles on the issue:
http://www.horsemagazine.com/CLINIC/...g/jumping.html
http://www.ansursaddle.com/AskAnne.htm
http://members.tripod.com/~TheHorseD...schooling.html
http://showrider.com/showrider/jumperridingtips1.htm - Part 1
http://showrider.com/showrider/jumperridingtips2.htm - Part 2

Wow! Thank you so much for your advice and for the articles you attached! I read them and they had JUST the info I was looking for. Thank you!