Hampton Landmarks (yes, sponsored by Hampton Hotels) has a huge searchable database of US landmarks, complete with photo and descriptions.
For example, take this one along I-10 in Cabazon, California: Dinny the dinosaur.
You may not realize it, but you’ve probably seen them in movies and commercials for years -- they’re the dinosaurs of Cabazon. Claude Bell, who ran the Wheel Inn Restaurant on I-10 alongside the beasts, built them. Bell spent 11 years building Dinny, a giant Apatosaurus and arguably the largest dinosaur in America. A small museum in Dinny’s belly still sells souvenirs. A giant Tyrannosaurus was Bell’s next project, and was completed after Bell’s death.
Very useful! http://www.hamptonlandmarks.com/ - Thanks Ian Jeffries!
http://roadsideamerica.com/