If you contact just about any farmer in the Yakima valley I think you would be received pretty well. I think it was a grape or apple farmer that let me and my Dad shoot them as much as we wanted, and paid us $.10 for each body we brought him. Paid for some of our ammo, I think the .22 we were using was about $.04 per round, but it was obviously just for fun and helping him out. He hated those little buggers. Sure wish I could remember where on earth that was...
Also, I worked with a guy who used to shoot them in Idaho a lot, and he found spots by calling county and farming town sheriff's offices and asked them if any of their deputies knew of good spots. He said that yielded the best spots he ever had ever been able to shoot on.
