Transmittal and Certificate of Achievement awarded to Sergeant Elvis A. Presley …”in recognition of faithful and efficient performance of duty and for outstanding service to the United States Army.”, 02/24/1960
This was fun to see about Elvis. There have been a number of famous people in the military, you can read brief accounts of them at http://www.army.mil/article/18424/, an Army media article.
This one page article offers a few details about celebrities who were in the US military. People covered include Werner Klemperer, Jimmy Stewart (retired as brigadier general), Rocky Blier (bronze star), Charles Durning (gold star), and Eddie Albert (bronze star). With some perseverance, you might be able to pull up the commendations for Blier, Durning and Albert by browsing through the Army’s General Orders at http://armypubs.army.mil/epubs/da_general_orders_1.html. These General Orders covered awards for all services. Unfortunately they are not searchable, but must be browsed by year and order number.