Try the National Archives.
This link will take you right to the page where you can either download or order the appropriate forms needed to request military records.
NARA | Research Room | Access to Military Service and Pension Records: This is one of best places to find info. You can download the proper forms here to order service records. The NARA has never let me down.
Here is more input:
- aad.archives.gov has some searchable databases although they havent any service records since the fire in 1973 destroyed nearly 92% of all Army/AirForce service records. Choose your subject and prepare for lots of reading.
- If you have copies of discharge papers it will have the division, etc. the person was in. My father was in the 2nd infantry division, 23rd regiment. The Army/Navy published history books in 1946 and I just found a copy "The Second Division in World War II". It is a very interesting book with maps, statistics, etc. telling the story of the 3 regiments in the second division. It has the names of all soldiers who died during the war and tells stories of all the battles. My father received the Distinguished Service Cross and this book describes what he did to receive it. This book was just re-published in 2000 by Battery Press, Inc. If interested in this type of book try searching World War II books for the division the person was in. This book was also listed under "The Combat History of the Second Division in World War II".
- Visit your local Veterans of Foreign Wars or American Legion Hall. Most towns have one. They are places where veterans gather a few times a month, and "remember". They hold patriotic ceremonies on war holidays such as Veterans Day, 4th of July, Memorial Day, etc. If you find the address for your local veterans organization, I'm sure you could visit, and ask them questions, and get more info.