I'm planning a road trip through the Southwest U.S., stopping at a lot of national parks and historical sites (click for details):
I'd like to listen to audio books while driving, about the history of the region -- both geological and anthropological. There are a lot of Navajo, Apacha and Hopi sites on the route, a lot of old Pueblo ruins, etc., so I'd like to know more about Native American history, from pre-Columbian times (if possible) up to modern days. I'd also like to learn about the geological history and structures in the region, e.g. the Moenkopi formation, the different strata, when they were laid down, all of that.
Audio books would be preferable -- but, really, any books will do, for bedtime reading between day trips.