The Library of Congress has an Authorities file posted at
http://authorities.loc.gov/. This database includes over 5 million
name authority records and 265,000 subject authority records with
references and scope notes. The service has recently been released to
the public for free access as a trial and they are still resolving a
few system problems. You will get more details on the known problems
and what is not included when you access Search Authorities from the
front page.

Authority Headings can be searched by Subject, Name, Title or
Name/Title. Searching tips are listed on the search page. Names are
searched with last name first, such as Hitchcock Alfred. The listed
records indicate which are Authorized Headings and how many
bibliographic records are under each heading. Records include a LCCN
and the fields listed by number. A selected record can be printed,
saved or e-mailed.