talking about natural horsemanship, I recommend Donald Newe's clinics! He is a brilliant instructor and does workshops/clinics & private sessions world-wide, just ask for it! He really concentrates on understanding the behavior of the horse and achieving full trust with the animal without any use of force. This all by using bitless bridle method, which causes no pain for the horse! You can check out his website for more information:
Equine Behaviour - Donald Newe comportementaliste Equin
Equine Behaviour - Donald Newe comportementaliste Equin