I always knew my father served in WWII and drove a tank but I never knew much about what he had done and where he had served. Now that I am very interested, my father is gone and I can’t ask him those questions. I recently saw my Aunt Barbara, my father’s only sister, and she told me that he had served under General George S. Patton and had fought in the Battle of the Bulge. What priceless information! Now I am on a quest to research Gen. Patton, the Battle of the Bulge, and my father’s role in the war.
Wandering Through My Roots 
I know some of the military files are lost, but you should try locating his file at NARA.
Yes, I have sent for them. They did say that many were lost but for “only” $25 I can see what they have reconstructed. $25 to find out his military history is cheap but $25 to get name rank and serial number will hurt. We’ll see what they send back.