Browsing can familiarize you with the scope of your subject area. The main book collection is located on the 3rd floor of the library. A call number is like a book's address. Here are some book neighborhoods you might want to browse:
J General Legislative & Executive Papers
JA Political Science (General)
JC Political Theory. The State. Theories of the State
JF Political Institutions & Public Administration
JJ Political Institutions & Public Administration (North America)
JK Political Institutions & Public Administration (United States)
JL Political Institutions & Public Administration (Canada, Latin America, etc.)
JN Political Institutions & Public Administration (Europe)
JQ Political Institutions & Public Administration (Asia, Africa, Australia, Pacific Area, etc.)
JS Local Government. Municipal Government
JV Colonies & Colonization. Emigration & Immigration. International Migration