UO Libraries has hundreds of primary source collections (physical and online), and there are thousands of additional open (free) digital archives hosted by other universities and institutions. Click on the various geographical regions listed in the menu to see a selection of our resources, covering newspapers, audio recordings, historical documents, and other digitized objects.
To search the internet for other digital archives, try searching in your favorite search engine with your topic plus the term "digital archive" (with the quotation marks). You can also try adding: site:.org or site:.edu to try to limit your search by organization type. None of these search tricks is foolproof, but they should help narrow your results.