To search for resources in the MSU Libraries, use the library catalog. The catalog is a searchable listing of printed and electronic materials located in the MSU Libraries, including: books, journals, e-books, videos/DVDs/CDs, etc.
If you're trying to determine if the library has your textbook, you can search Course Reserves, searching by course number (i.e. psy 280) or by instructor (Thomas, Stephen). You can also request items from other libraries through interlibrary loan.
