Concert Band - Digital Download SKU: AX.00-PC-0014360_WPTBETC (wp) E-flat Tuba T.C.. Composed by Johnny Mercer. Arranged by Paul Cook. Instructional. World Part. 1 pages. Alfred Music - Digital Sheet Music #00-PC-0014360_wpTBETC. Published by Alfred Music - Digital Sheet Music (AX.00-PC-0014360_WPTBETC). UPC: 038081389493.I'm an Old Cowhand (from the Rio Grande) was written for the motion picture Rhythm on the Range by veteran songwriter Johnny Mercer. The song was sung by Bing Crosby and became a big hit. Many other singers and singing groups have recorded this song.