Check out a bow gunter by Away hunting. It has 4 diffrent settings, is hands free, you inhale instead of exhaling so it won't freeze when cold. It also comes with a 90 minute video about "social calling" and exploiting deer weaknessses. Great video, they take some dandy bucks. I definately learned some new stuff. They also cover making mock scrapes.

http://www.awayhunting.com/acatalog/

Check out the Bowgrunter Plus Video Combo Pack
It's 25$ for the bowgrunter and video.