Prefer this for simple searching and quick results in a library near you.  Advanced searchers may prefer the normal WorldCat, a subscription resource for SLU students, faculty, and staff.
WorldCat.org is a freely available version of the WorldCat database that includes all types of library materials cataloged by libraries that contribute their records to OCLC, the U.S. national database.  Use to search by subject, title, or person for books, recordings, videos, Web sites, etc.  Then, locate a library near you that owns the item you need.  (GB)