Jim,
Folkways is now called SMITHSONIAN FOLKWAYS. Google that and there they all will be. Even the one titled SOUNDS OF NORTH AMERICAN FROGS.

Another great record of Barbara Allen variants was issued on LP by the old Archive Of Folk Song at the Library Of Congress in Washington D.C. They are now the ARCHIVE OF FOLK CULTURE.

My favorite version on that album is sung unaccompanied by Rebecca Tarwater if I'm remembering it right. Several tracks were not complete but you did get to hear the tune and the singing style. But Ms Tarwater's singing of the ballad was the complete song---as were other exceptional field collected performances on the record.
I figure it ought to be a CD by now!

Art Thieme