I recomend the Hunter Specialties... Secrets of Turkey Calling made easy vollume 2. video.
I also recomend that you get an instruction tape for mouth calls that also has plenty of real turkey talk on it, and practice practice.
I found them more helpfull than others specialy with the mouth call. They helped me get my bird my first year. Keep in mind that you don't have to be the best caller, it's more important that you know your bird and when to be still. I recomend getting proficient with the glass call first such as the power crystal etc.,then moving on to others if you choose.
Good Luck
You can never have too many Turkey videos!