If you write either historical fiction or nonfiction, you need to become familiar with the Library of Congress. Their holdings are vast and they are making an effort to make more available online. Their digital collections can be found here and encompass social history, music and invention.
The newest collection to make its way into the digital universe are the Benjamin Franklin Papers. Click through and you can view approximately 8,000 most of which are from the 1770s and 1780s. The collection includes both his work in politics and his work in science and although not all of it is online, this is a start.
Additional collections include:
Alexander Bell Family Papers: The online collection contains about 51,500 images of correspondence, scientific notebooks, blueprints, and more.
After the Day of Infamy: These man-on-the-street interviews were recorded following the attack on Pearl Harbor. The collection consists of 12 hours total although I’m not sure how much has been digitized.
Ansel Adam’s Photographs of Japanese-American Internment at Manzanar : I just recently learned about these photos so I was excited to see that they can be found at the Library of Congress.
Explore the various collections and you will find sheet music, film, and more. Keep in mind that just because the material is available does not mean there is no copyright. But often the Library does not own the copyright so if you want to use an image in your work you may have to go through the effort of contacting the copy right holder.
Personally, that isn’t a problem for me because I tend to use the material here as inspiration. What would it be like to be a professional woman, a Red Cross instructor, interred at Manzanar? How natural were Curtis’ Native American portraits and how staged? Why would they have been staged? If they were, are they still valuable.
The next time you are stuck for something to write about, spend some time in the collections of the Library of Congress.