Check the Arkansas records, W.O. Coleman was a Confederate Regimental Commander. Sorry I can't recall the specific designation at this time and I lost all my reference material when my computer crashed.
I learned of Col. Coleman during my search into the history of a hometown Veteran named Captain George L. Herring. (I was at that time trying to identify the unit that killed him at St. James, Missouri in June of 1864).
Good luck.