Books often provide more detail and are more expansive than academic articles. Sometimes they are collections of papers or essays that are essentially what you would find as an academic article.
Library Search is the main tool for books in the Temple University Libraries system. The system uses the Library of Congress classification system, which uses letters and numbes to arrange books. Political Science is generally in the area of the call letters J, law is K, and country and state topics are generally in the range D-E-F.