Some selected new books are highlighted here.
Use the Library Catalog to search for these books by keyword.
One sample search might be something like: illinois AND (politic* OR govern*)
Or just the name of the topic: president
The asterisks at the end of the word are truncation features, and allow you to pick up variations of the word:
politic* without having to type out separately all the variations of a word.
Outline of the Library of Congress Classification System (what COD uses to arrange its books on the shelves).