On the AAA United States map, toll roads are orange. They are not as distinctive as on the Rand McNally atlas, because the AAA map uses red for the interstates.
Once you get your route established, go to AAA and get the maps for all of the states you are going to drive through. I find it extremely helpful to have both the atlas and the individual maps on our trip, as sometimes, one will show something that the other does not.
We use our GPS unit (or the GPS within our phones) only for finding an individual address within a city, such as a gas station, grocery store, restaurant, or hotel that isn't right next to the highway. You may find it handy to get directions to the college/university that you want to tour.
Donna