Primary sources are documents (letters, diaries, speeches, films, photgraphs, etc.) that were created during the historical period that you are studying. The Reference and User Services Association of the American Library Association has put together a guide that will help explain what primary sources are and how to go about finding, evaluating and citing them, particularly when they are on the web: Using Primary Sources on the Web.
The pull down menu on the Primary Sources tab will guide you to primary resources on the web organized by time period, geographic location, people, journal title, and subject. Also included is a link to our primary source microform collections. Cohen Library has a microform reader in the reference area on the 2nd floor as well as in the Archives. Although a bit more work than print or online sources, do not let this stop you from finding the perfect source for your research.