The Library of Congress’ “Chronicling America” Web site, freely available at http://chroniclingamerica.loc.gov/, has added 287,000 newspaper images from 15 states and DC, which brings the
total on the site to 1.7 million pages from 212 newspaper titles published between 1880 and 1922. I reviwed the site back in May so I’m not going to get deeply into it again, but I did want to mention a few things.
If you’re less interested in the text in the newspapers and more into the illustrations, don’t miss this set on Flickr called “Illustrated Newspaper Supplements”. 364 images ranging from people to places to events to an odd picture of a very small lady and a very large dog.
Chronicling America also has an API; you can get information on that at http://chroniclingamerica.loc.gov/about/api/. The syntax for the API seems pretty simple (and you don’t need an API key!) You can search for keywords, link to particular pages, etc.
If you want to get an idea of what’s available in the archives, but you can’t think of any good search terms, visit the topics list at http://www.loc.gov/rr/news/topics/topics.html. It’s pretty abbreviated — less than two dozen topics — but each one provides useful dates, suggested search terms, and a list of sample articles.