Bob,
I grew up in St. Louis, but had 4 grandparents in Springfield. We took the train or drove there every month (on Highway 66/I-44) while I was a kid, either stopping in Rolla to change drivers, or riding through on the Frisco. Small world!
The Ozark Mountains seem like the center of the world to me, even though I live in suburban Boston now. As a boy, I rode behind steam locos in the 40's and later mostly diesels. I was also lucky enough to ride "name" trains from St. Louis to New York, Washington, New Orleans, Los Angeles, and a number of other destinations, on the Texas Special, Panama Limited, Twentieth Century Limited, Spirit of St. Louis, Broadway Limited, and others. My dad had a very good pass for the whole family, and I got some excellent rides.
Let us know how your model railroading goes. By the way, when you're laying out your curves, if you use a transition curve of larger radius (even 1/2") for several inches at each end of a curve, the whole curve will function like a larger radius curve--it's easy with flex track, and so effective it seems like cheating. John Armstrong describes the technique in his books, as do others.
Bob McD