Finding books on the Internet has become easier thanks to Google book search. This search service gives lots of information about new and old books. You can find free books that are out of print, but there is also a lot of data about new books that you can buy online or in your local bookstore.
Now, Google is even integrating their maps technology into Google book search. If you search a book that mention several different places, you will see a world map, and resulting listing what places in the world the book is referencing.
This doesn't seem very useful for most books, but certainly there are some books where it will be interesting to see where the action occurs. In the Google book search blog you will see a better example, involving different foods over the world:
As of yesterday, this sort of information became a lot easier to find as well as visualize: there's now a Book Search feature on the "About this book" page which shows readers the places mentioned in a particular book and pinpoints them on a map. Clicking around on the map for Extreme Cuisine, I quickly found out that dogs are on the menu in Seoul, Roman emperors enjoyed dormice, Melbourne residents serve up emu and crocodile, and Mopani worms are available in Johannesburg!