He received his masters from UK and went on to become an associate music professor of trumpet at Michigan State University. He is a member of the faculty quintet "Beaumont Brass" at the Michigan State University College of Music.
Illman is former principal trumpet for the Lexington Philharmonic Orchestra, the Lexington Brass Quintet, and soloist with the Kentuckiana Brass. He has performed in the bands of Ray Charles, Doc Severinson, and Burt Bacharach. Illman is a former faculty member of Eastern Kentucky University (Richmond, Kentucky), the University of Kentucky (Lexington, Kentucky), Transylvania University (Lexington, Kentucky) and Asbury College (Wilmore, Kentucky).