Look in the Yellow Pages.
Also, not sure whereabouts you are, I've found the Hutterite colonies to be good places to buy turkey. They sell me Utility Grade birds for a reasonable price. I'm very
sure to not
tell them that I am using the turkeys for my dogs. I'm always paranoid that if I tell people it is for my dogs that they will sell me "not for human consumption" birds. My butcher knows though, it is hard to explain why I would want them ground bone-in otherwise.
I trust him though, I buy all my meats there.