I am no expert on PD's. I'm from New England where most shots at anything are under 50 yards, but I have gone a number of times across the big river and have been successful.
First of all, I would surf the net and look at potential locations. It seems that North and South Dakota offer good hunting without having to pay an access fee or use a guide. In discussions with other hunters in South Dakota, they all pretty much said that the ranchers would welcome you with open arms. Personally, I have only hunted on public land. I kind of went cold into an area and asked some people at the bars or at sporting good stores. They kind of steered me in the right direction.
You can also contact a county courthouse and ask if ranchers have put in any complaints and if they know of ranchers willing to have hunters come on their property. I spoke with one courthouse worker who told me of one ranch that had problems. I went there but no one was home and I had a schedule to meet.
This past summer I shot some in North Dakota on public land. I was showing my girlfriend the Great Plains and she had limited time. Otherwise if I was alone, I'd be there for a solid week just shooting PD's and doing some PR with the local ranchers. But youy should have no problem finding PD's on public land.
A good map from a county agency will show who owns what.
As far as what to do. Well, I didn't know what they looked like until I drove around and looked for their burrows or towns. When you look over the open ground, the plains have different hues of green and gold. The mounds look like whitish/light brown pock marks. In a way from a distance they look like a dead spot on a lawn. What you do then is look at the mound or hole with binoculars to see if they're out. Like most animals , I discovered they are morning and afternoon creatures. When I hunted it was very hot and I didn't see them out much in the dead noon heat. But I may be wrong.
I have seen them in the Badlands of North Dakota. In addition, the national grasslands near Ft. Pierre, South Dakota have them. You need to get a grasslands map and start going out on the roads and looking for those pock marks. I have also seen them along Rte 90 crossing the state of South Dakota.
The way I would hunt them with the TC Contender is to try to get above them on a high hill and shoot down at them from a concealed position. I would use my medium ALICE pack as a shooting rest with great success. I had a ball with the 22 WRM and next time I will be using a 17 HRM.
I wish you well on your endevors to shoot these little varmints.