We have had a problem with them on our deer lease for two years now. They come to the feeders and are easy to lure if you are not hunting them. Once a couple have been shot they become quite nocturnal and much less visible.
There are several products to attract them like "Pig Out" that you mix with corn, or pour in a wallow to attract them. Others just use smelly garbage or a bucket of wet soured corn. All work when they are in the area.
Problem we have found is that apparently they range widely and will be in one area today and perhaps several miles away the next. We shoot them whenever we see them in order to try to keep them in check, but they multiply like rabbits so it is an unending effort.
Oh, by the way. They are hard to clean, but really, really, really good eating!!! Not nearly as much fat as commercial pork and unless you get a very large old boar that stinks to high heaven, they are prime eatin'. Good ground into sausage and grilled loin is fabulous. I cook chunks of the pork in the crock pot with pineapple, sweetener, Worcestershire sauce, onions and peppers and serve it over rice. That Hawaiian pork is hard to beat and refused by nobody. Given the choice for both I will shoot the pig before the deer to fill the freezer.