"More Than a Song" was published in the UK under the somewhat misleading title of "The Folk Music Encyclopaedia" (Omnibus Press 1977).

Here are some others from my shelf:

How Can I Keep From Singing: Pete Seeger, by David King Dunaway
   (McGraw-Hill, 1981)

Lonesome Traveler: The Life of Lee Hays, by Doris Willens
   (Norton, 1988)

Charles Seeger: A Life in American Music, by Ann M. Pescatello
   (University of Pittsburgh Press, 1992)

Singing Family of the Cumberlands, by Jean Ritchie
   (Oxford University Press, 1955)

Cecil Sharp: His Life and Work, byu Maud Karpeles
   (University of Chicago Press, 1967)

Radio's 'Kentucky Mountain Boy' Bradley Kincaid, by Loyal Jones
   (Appalachian Center/Berea College, 1980

As Far As the Eye Can Sing, by Frankie Armstrong with Jenny Pearson
   (The Womens' Press, 1992