American Treasures of the Library of Congress: Bas
Includes sheet music covers of several baseball songs, the first of which was written in 1858.
Classic Railroad Songs
Collections of songs since 1930, including historical profiles of song and CD ordering.
Froggy's Novelty Song Lyric Collection
Songs popular during the first third of the twentieth century as transcribed from period phonograph recordings.
I Hear America Singing: Patriotic Melodies
Includes stories behind the songs, audio samples, and sheet music.
Popmatters: Freight Train Blues: Classic Railroad
Mitchell Moore's review of the CD released in 2000.
Slate: The Worst Songwriter of All Time
Mark Steyn's article on Bob Merrill and novelty songs in general.