The books in the catalog are tagged with phrases called "subject headings" that describe what each book is about. To search the subject headings, go to the catalog's Keyword Search page and select “Subject” from the drop-down menu. Or, choose from the list below.
Most of the sources you find will include lists of citations (a.k.a. bibliographies). Think of these citations as low-tech hyperlinks -- they point you to other sources on the same topic. Follow those links! When you look at all the sources as a whole, they form an interlinked network of information. Your job is to explore that network and see what else is out there.
If you've found a good book or article, and you'd like to find newer sources that cite that particular book or article, type the title into Google Scholar. Then, on the results page, click "Cited by."
Use the library catalog to find books. When you find a book in the catalog, click "Items" to see where it is in the building, and whether it's checked out. Write down two things, the location and the call number.
Here's a map of Simpson Library, in PDF format.