Wilhelmi began his artistic career as an illustrator and graphic designer. He attended Montana State University and the University of Denver to get his degree in art and later became a tenured faculty member at Colorado Institute of Art. His work is represented in hundreds of corporate and private collections.
After 25 years, Wilhelmi closed his Denver studio and returned to Montana where he had grown up and where he has always received inspiration from the land. He now lives and works close to Roundup.