Don't confine your research just to sources available at Rutgers. WorldCat is a worldwide library catalog, much, much larger than the Rutgers catalog. Make sure to use the version of WorldCat that you access from the Libraries Databases page. It has features available to you as a Rutgers student that are not available in the free version, worldcat.org.
Go to Advanced Search. There you could search, for example, "black panther party" as author and then add additional keywords. In the results list, at the top of the page, you'll see tabs that allow you to limit the results to certain types of material. For example, Archival will give you records for original documents-- letters, diaries, internal reports-- held in a library's archives. Get in touch if you have questions about using archival material. Archival collections are often an excellent primary source and are fun to use.
You can limit your search to primary sources by selecting, in Advanced Search, Subject in the drop-down to the right of one of the search boxes and then searching: sources or archives or correspondence or diaries or speeches or interviews or oral or newspapers.
Items that Rutgers Libraries own will have a Rutgers icon as part of the record. Click the title to go to the full record, then click Get@R. That should give you the record in QuickSearch. If you want to try to arrange an interlibrary loan for something we don't have, in the full record, click Request Interlibrary Loan. You'll be prompted to log in with netid. That will automatically fill out a request form and you just need to click Submit to initiate the request. You will probably have to wait one or two weeks for an interlibrary loan, and it's possible you won't get it at all; if it's a rare item, we may not find a library willing to loan it.
If you have any questions about WorldCat, click the Email Me, below the Your Footnotes, Bibliography tab.