Try a different approach. Maybe run an ad in the local paper? I think the best thing to do is establish a relationship with the landowner and give something back in exchange for use of their land. Put yourself in their place. What would you do if you owned property and some stranger, of which you have no clue about and what their history is, comes to your door asking if they can walk around your property with a weapon? It's not like turkey are going to eat up their crops so you have to think of some other incentive. Either that or you will probably have to just lease land to hunt on or join a hunting organization which does the same for its members.