In this column: blues enthusiasts, folklorists, musicologists, Ruby Tartt, Works Progress Administration, John and Alan Lomax, Sumter County (Alabama), Library Of Congress, Vera Hall, Elie Siegmeister, Byron Arnold, Carl Sandburg, The American Songbag, Harold Courlander, Folk Music U.S.A., Ruby Terrill Lomax, Delta Kappa Gamma Society, Al Brite, John Heathcock, J.M. Mills, Bess Hawes Lomax, The …