I have quite an extensive collection of Czech and Moravian folk music as recorded by the group Cechomor. Unfortunately I don't have any "source" recordings.

It is worth listening in conjuction with Middle Europe history - a few weeks ago I found a web page that showed the political boundaries at the turn of each century since the Roman Empire. I'll try and find it again.

I am not too familiar with the timeline of American history, so for a point of reference about what century/decade would the migration have occurred? Possibly it may coincide with the acscendency of the Austro-Hungarian empire.