I'm not sure how GPS works but in all seriousness, all you need to do is get a good old fashioned paper map from your local store and roads are marked paved or dirt, at least the roads on the map are, small, county or township roads may not be on the map depending on how big the state is and how much info they can get onto the paper without the print being too small. You may also want to look into something called a "gazetteer" check the spelling, that breaks a state into grids and show EVERY single road in the state, paved or dirt. Good luck, I recently got lost in rural Ohio Holmes county on the tertiary roads that were basically kinda paved 1 1/2 lane buggy trails, when I got home, all of them were marked on my Gazetteer.