America at War, 1941-1945 - World War II documents from Boatwright Library Federal Depository Collection at the University of Richamond. Focus is on the daily life of the soldier.

Government Documents A to Z Digitization Project at University of North Texas has two collections of note:

• War Department Field Manuals
• War Department Technical Manuals

Historic Government Documents from World War II - contains 343 information pamphlets, government reports, instructions, regulations, declarations, speeches, and propaganda materials distributed by the U.s. Government Printing Office during WWII. A digital initiative of Southern Methodist University, Dallas Texas.

Here are some digitized primary source materials you can access online.

American Memory War and Military Collections (from the Library of Congress)

Historical Text Archive articles, books, essays, documents, historical photos, and links, screened for content, for a broad range of historical subjects.

National Archives and Record Administration (NARA) The archive of the United States, including many military and veterans' service records

The National Union Catalog of Manuscript Collections

Link to The Valley Library's Government Information Guide for access to a wide range of resources pertaining to government information. Some of the most useful for defense science and education are:

Defense Technical Information Center (DTIC) serves the DoD community as the largest central resource for DoD and government-funded scientific, technical, engineering, and business related information available (full text available) 

Federal Aviation Administration Regulations 

FDsys is the primary public access to Government information submitted by Congress and Federal agencies. Featured collections include Code of Federal Regulations; United States Code; Federal Register; Congressional Bills, Documents, Hearings and Reports; Congressional Record; Compilation of Presidential Documents; Economic Indicators; Public and Private Laws.

Catalog of U.S. Government Publications (CGP) is the finding tool for federal publications that includes descriptive records for historical and current publications and provides direct links to those that are available online. Users can search by authoring agency, title, subject, and general key word, or click on "Advanced Search" for more options.

Department of Defense (DoD) website   Includes links to all the military services websites

Department of Defense information from USA.gov