Bread's "Truckin'" comes to mind.
John Denver's "Matthew" ("gold is just a windy Kansas wheat field, blue was just a Kansas summer sky")
And our family favorite, the song "Oklahoma" (from Rodger & Hammerstein's musical of the same name) as one crosses the state line into that state.
"Deep in the Heart of Texas" or "Yellow Rose of Texas" when traveling through that state.
"City of New Orleans" (either Arlo Guthrie or John Denver)
"St Louis Blues" (almost any version) as one pulls into St Louis
"Chicago" and "New York, NY" (Frank Sinatra) as you pull into either of those cities.
Donna