A secondary source is one that was created after the event by someone who wasn't there. Examples include books, journals, magazines and websites. It isn't one that is secondary in importance!
You can find books online:
UHS library - we have many books with general information on the Middle East and Islam, as well as country and topic specific ones.
The best place to look for journals and magazine articles for your research paper is through the UHS library databases (a database is an organized collection of pre-selected resources). Make sure you are looking at an article NOT a book review (though you can look for the book if it sounds worthwhile):
Look at the SFPL Libguide for resources available through the San Francisco Public Library. You will need your card number and PIN to access them. As well as access to ebooks, SFPL has many databases that we don't have including Hoopla.