"Letter From America" by the Proclaimers is a song telling of a persons's migration from Scotland to the USA.
Are there other songs relation to migration not only referring to Scotland to the USA but from other areas to places around the world or even within nations?
Yeah I suppose, but it's the only one I could think of that's remotely near, Leaving On A Jet Plane might fit, you can read into those lyrics what you like.
There's a whole CD by Phil Coulter and James Galway, called Winter's Crossing, which is traditional music of the Irish immigrants to the USA. Most of the tracks are instrumental (and very haunting), but there are a couple with vocals. I'm not sure how to post links, but I'm sure googling it would find the full listing.