You actually can find a lot of primary sources online through digital libraries. The websites below are a good place to start when looking for research about California and the U.S. in general. Sources include, but aren't limited to: photographs, audio recordings, films, books, and certain documents (like correspondence, reports, meeting minutes, etc.).
- California Digital Newspaper Collection - A freely accessible repository of digitized California newspapers from 1846 to the present. This collection contains 184,777 issues comprising 1,956,297 pages and 16,861,779.
- Calisphere: California Digital Library - Calisphere is a gateway to digital collections from California's great libraries, archives, and museums. Discover over 400,000 images, texts, and recordings--and counting.
- HathiTrust Digital Library - HathiTrust is a partnership of academic and research institutions, offering a collection of millions of titles digitized from libraries around the world.
- Internet Archive: Digital Library - Internet Archive is a non-profit library of millions of free books, movies, software, music, websites, and more.
- Online Archive of California (OAC) is a research gateway to unique and historical materials at archives, libraries and museums throughout California.
- UCLA Library Digital Collections - UCLA Library provides a web presence for digitall content accepted into, or developed by the Library.
- WorldCat - is the world's largest network of library content and services. WorldCat libraries are dedicated to providingaccess to their resources on the Web, where most people start their search for information.