The Library Staff is one of the most overlooked resources in a library. The fact is they are constantly working with its catalogs, reference books and databases and know and them inside and out. As a rule they are generally aware of new additions to their collections before they are even entered into the catalog.
In larger libraries, you'll find librarians whose sole responsibility is to work in specialized departments like the social sciences reference desk or the government documents section. If you need help locating materials, need to learn how to use a particular database or just simply want to know how to use the catalog ask a librarian. They are there to help.