Building Confidence Workshop/Resisting Distractions

I would like it if there was a workshop in which we teach our dogs to not be afraid of unusual things like things falling with a loud bang, and unusual situations like being at the vet or groomers. I would like for our dogs to learn to happily stay focused even when there are noises and movements around whether pleasant or unpleasant for the dog. I am trying ot raise my dog to be a therapy dog and she has some things that we need to work on.