Neat thread. I'm booking and hosting a music series here in Brantford (Ontario) called the "Sunday Roots Revival" at a place called the Station Coffee House & Gallery . It's actually in an active CN/VIA Rail station (used to be the the luggage office, in fact).

As a result, my current duo Jericho is always on the lookout for train songs.

Here's some I didn't notice on the listings thus far:

by Fred Eaglesmith: "Freight Train" (recently recorded by Alan Jackson as the title song for his new CD)
and "I Like Trains" (there's a sound bite of it on our Jericho website)

Rankin Family - Orangedale Whistle, written by Jimmy Rankin

Murray McLauchlan - I Never Did Like That Train

Somebody also mentioned "Hank Snow's Canadian Pacific" - written by Ray Griff, also recorded by George Hamilton IV on an album called "Canadian Pacific" back in the late 60's. (Also on the album was 'Steel Rail Blues' recorded in a room in the old Seaway Hotel (Toronto) with Gordon Lightfoot playing back-up guitar!)