Watched a Cesar Millan recently where he had a VERY nervous dog to be groomed. The key seemed to be an emotional detachment on the part of the groomer, not reacting to the dogs nervousness, a sort of 'jolly hockey sticks' approach to just getting on with it.
If you get nervous and stressed while trying to groom the dog, the dog picks up on that and gets more nervous and stressed.
Im sure pretty much any experienced groomer would (or should) be able to handle a nervous dog. The first time is going to be the worst for the dog, should get easier after that.