Some natural horsemanship is really great stuff and other people's methods are just weird. So be careful what you get started in and don't choose something just because many other people use it. I reccomend Monty Roberts' methods: his website is www.montyroberts.com
and all of his methods are explained in his book, The Man Who Listens To Horses.
He started by observing mustangs in Nevada and watched their means of communication, then turned it into a method for quickly and completely gaining a horse's trust by just running it around in a round pen, using specific body language cues that a mare uses on an ornery colt to ask the horse to put his trust in you. It takes one session to noticably gain more trust from your horse...I have used it on all my horses, from a little western Mustang to eventing TBs to a Warmblood to a dressage Arab cross to minis, and it really works. I think his is one of the best methods out there. :)
Hope this helps.