That's an easy one to get hold of nowadays. It is on Rounder CD 1059, Jimmie Rodgers, 1929-1930, Riding High, which is volume 4 in their series of the complete Jimmie Rodgers. The same material is also available from Bear Family as a boxed set.

There is also an interesting version of Answer To 'Moonlight And Skies' from 1944 on Bear Family CD 15580, Jack Guthrie, Oklahoma Hills