Our school IU (intermediate unit) has a roster of artists. (I am in PA) My district also gives me the option of using an unrostered artist, provided they have all their clearances. That would probably be a good place to start. Like someone else shared, if the residency is a certain length, the IU picks up half the tab.
All of the residencies I have had have gone quite smoothly. I would recommend it highly. We have created some very cool permanent art for the building>