If you are searching for a (not brand new) book or an article that is not in the Delaware Library Catalog, we can make a request to other libraries through the Interlibrary Loan service. Each library has a process set up to help expedite such requests, but it's helpful to know if the item is available through the University of Delaware's library or another nearby (out-of-state) library.
One way to check for yourself is to use WorldCat. This online catalog shows items from many libraries - mostly academic - but please be aware that it is not inclusive of all libraries. So the results are limited, but it can be helpful and of interest to see.
Some Delaware libraries have an Interlibrary Loan Policy posted online which offers further details. For example, here is New Castle County's ILL policy found on the New Castle County Libraries webpage on "Policies and Forms."
For most of Delaware public libraries, Interlibrary loan requests can be submitted in person, over the phone, or through our Ask a Librarian Delaware service. Here is a list of Delaware's libraries, with hours and locations.