The Archives of Appalachia is a repository for items from East Tennessee and the greater Appalachian region. Here you may find hundreds of thousands of photographs, manuscripts, audio recordings, and more. Highlighted relevant collections and exhibits include:
The Washington County Archives house some of the oldest records in the state of Tennessee. Materials include manuscripts, photographs, books, maps, microfilm and more.
The Tennessee Virtual Archive holds material from the entire state of Tennessee. As you seek to contextualize the Appalachian experience, this may be a useful resource.
For primary source material from a broad, American, perspective, check out the National Archives. As the scope of your research expands into contextualization, you may want to use this resource.