Google has decided to end its newspaper digitization project. Existing content, about 60 million pages from 2,000 newspapers, will remain available, but no new content will be added. See American Libraries article. (5/24/2011)
Depending on the database, you may need to refine your results to search for newspaper sources only. In most databases, this can be done by:
However, most of the links within this guide will lead you directly to Newspaper refined results of the database.