I don't know if anyone "hunts" prairie dogs - we just get out of the truck and shoot them while sucking on a cold mountain dew.
If only deer were that easy.
Anyways, I have only been once, but I loved it. I think we are going again early this summer.
We went in SD, near Chamberlain. We stayed in a hotel on the reservation near there. We would usually pack sandwiches for lunch, or drive into Chamberlain to eat. There are a few public areas there, but the dogs there were about as "smart" as they get. They would hear the car doors, and start getting into the ground. We also shot some on different rancher's land. Either they would hear us shoot and invite us onto their land, or we would just go ask. A couple of times, they would call neighbors and try to send us over to the neighbor's land. It was easier to get permission to shoot them there, than it is to get permission to hunt rabbits here. People would literally drive up to us, tell us where their property is, and invite us to shoot all we wanted. Point being - a guide is not needed there, but plenty of drunks would off to guide us.
I know you may not want to roll the dice and find out that is not the case for you, but I have read a couple of threads here where people have said the same thing.
Maybe you could call the chamber of commerce in some areas, and see if they have any leads. I would bet that they get asked that frequently enough to have an answer for you. Maybe they could put you in contact with some ranchers, and you could work something out with them directly.