I went to a Micheal Peace demo and it was really good! There was one horse that was absolutely TERRIFIED of clippers. Michael had a 10 ft rope and turned them on and the horse started cantering around the school! But in about 40 mins, he was running the clippers (on) down the horses neck ( this horse now looked like an old pro).
His books good too, very easy to understand

and you don't need any expensive equipment

.
Well worth seeing if you can.