I know it is called “Trumpet March” and it is for a flute duet.
I need to know the composer and/or where I can buy the sheet music. I used to play this with my flute instructor and I’d like to practice it again.
With the wealth of knowledge here I don’t suspect it will take very long . 
I’m pretty darn good with classical music (broadly interpreted) and I’d never heard this’n before! Quite pretty!
It apparently comes from Volume 1 of H. Voxman’s “Selected Duets for Flute”, Rubank Educational Library #177: #13, p. 19, “A Trumpet March”.
The sources of Voxman’s selections are listed here, but I’m not sure there’s a way to tell which one the “Trumpet March” is taken from without looking at Voxman’s book:
Thank Kimstu!! Now that I know the book I can track it down from here. That is exactly what I need.
No problem! 
Nice piece of music, too. Happy flauting! (Fluting? Piping? Whatevs.)
The correct term is “blowing gently on firm rods” but it sounds better in Latin.
Order it off Amazon so I should get it in a few days. Thanks again!
Great! When you get the book, please tell us which of those classical compositions Voxman’s flute-duet adaptation comes from; it would be interesting to hear the theme in the original work.
I picked up the book at a local music shop and the song is in the chapter “Seventeen Duos (Arranged from the Works of Anonymous Eighteenth Century Composers)”. So I guess there’s no way to know who did the original, it has been lost to the sands of time.