You can find some primary sources in books. Below is a list of relevant subject headings. When searching for these in the catalog, try adding "sources", "documents", "correspondence", "letters", or "writings" to your search.
A digital library of Internet sites and other cultural artifacts in digital form. Includes digitized books, periodicals, media, and more.
A repository for digital collections. Items in the public domain (works published before 1923) are freely accessible online.