In addition to print books, the ULS provides access to a large number of e-books. You can access e-books in PITTCat+.
Note that if you are off-campus, Search as you normally do and click on the link to the full-text ebook. PITTCat+ will prompt you to log in with your Pitt email login and password. Then you're good to go for your entire searching session! Access will work best if you stay in the same browser. For additional information about setiing up your the EZproxy log in see the instructions here.
Here are other Libguides that may interest you.
Search Google Books to find books on your topic of interest.