I'm just back from travelling to California and New Jersey. (I have lived in each place, in case you're wondering why I chose those spots.) Before a trip, I like to check out a couple of books on the places I plan to visit. Everyone knows the BIG spots to see--Golden Gate Bridge in San Francisco and maybe the Asbury Park Boardwalk in NJ. But a little research points me to some new and surprising gems for my travels. Sometimes a county park or a tiny museum becomes the highlight of the journey.
The travel books are set up geographically according to the Dewey system. It's not so easy to find particular places until you figure out the system. But at least California and Las Vegas are near each other, suggesting a side trip!