Maud Karpeles published a short piece, A Return Visit to the Appalachian Mountains, in the Journal of the English Folk Dance and Song Society (vol.6, no.3, 1951) describing her three-and-a-half week trip.  Some 50 of the singers recorded by her and Cecil Sharp had died or disappeared, but she managed to find 31 (original singers or their near relatives), and recorded material from a further 5 singers and instrumentalists.  34 of the songs had been noted on the previous trip, and published in English Folk Songs from the Southern Appalachians (1932), but at the time of writing she had not had the opportunity of transcribing the new recordings to see exactly how they had changed over the intervening years.

The article included transcriptions of four songs not previously noted; The Gypsy Laddie, from Mrs. Donald Shelton (née Emma Hensley); The Cruel Ship's Carpenter from Mrs. Charlie Noel of Hot Springs, N.C.; Rock-a-Bye Baby and Down in the Meadow from Mrs. Oscar Allen (née Ada Maddox) of Lynchburg, Va.

If you'd like a copy of the article, let me know.