Springfield, Oregon was recently confirmed to be the real life small town inspiration for the Simpsons. You won't find any bright yellow people here but you will find Springfield museum where you can find out about the social history of the town. This includes mention of the rivalry that existed with near neighbour Eugene - better known to Simpson's fans as Shelbyville. You can also pick up a guide to the main street of the town which points out some gems including the archetypal railroad station and a lovely art deco Buic dealership.
Google map: bit.ly/WGpShR