Everywhere! Books are located on the 3rd, 4th, and 5th floor. There are several different collections. Take a look at this guide to see where each collection is located.
Most of the time you're probably going to be looking for books in the collection called "Stacks". This is the main collection of books that you can checkout, and it's located on the 4th and 5th floors. Use the Library Catalog to find out what books we have or take a week to browse our collection of more than 570,000 volumes.