It is time to contribute to this fantastic thread. I do not believe any of these have been mentioned yet, apologies if they already were.
I have linked all the songs, just click on the song to go to the YouTube page:
Railroad Man - Johnny Criner Quintet
Who am I Rollin' By - @Arnold D. Cribari
The Ballad of the Southern Pacific - Steve Spurgin
Counting Those Railroad Cars - James Coffeey
Where do ya work'a John - Marrill Jay Singers (This is very odd/interesting one.........)
Kundalini Express - Love and Rockets
Waiting for a Train - Gene Autry
Night Train to Memphis - Roy Acuff
Ballad of 611 - Norfolk Southern (Made for '91 anniversary)
This is a full album from James Brian Coffeey, he did most (if not all?) of the songs for the popular "I love Toy Trains" show from TM Books & Videos.
The songs are aimed towards children but they are very catchy. A few of my favorites: Streamliners, Big Train a Comin' , Toy Train Hall of Fame, Ghosts of the Rails, & Freedom Train
Enjoy!
Bryce