Try to listen to real turkeys for your sounds and rythyms. As far as listening to contest callers you can get an idea of what a routine should consist of and how long to run each series of calls. But you should always try to sound like a real turkey and not your favorite caller.
I started out taking videos of every contest I entered just to see about the routines.
There is a lot of practice put into a good contest calling routine.
Remember you are calling to impress judges not to kill a gobbler. Good luck....