The Simpsons by Antonia Coffman, Matt Groening, Ray Richmond (1997, Paperback)

A running joke throughout the series is that no one knows where Springfield is. The writers are always coming up with ways to keep the audience guessing. Some examples of this are: in 'Sunday, Cruddy Sunday' when Marge phones the egg painting company and gives her address, she says, "742 Evergreen Terrace, Springfield Ohi...", then cuts out to say, "Oh hiya Maude!" to Maude Flanders, who suddenly appears in the kitchen. When Homer and Bart are off to the Edison Museum in 'The Wizard of Evergreen Terrace' they drive past a sign with exits to New Jersey, Michigan and Oregon, none of which are close to each other. When Larry Burns spots Mr. Burns on the train, he asks where the train is going. The conductor says, "Springfield." and Burns asks, "Springfield where?", but the conductor's reply is drowned out by the train's engine.