Because the notification process isn't working at Google Answers, I'm
going to take a chance and post an Answer to your question. I strongly
believe it will be what you're looking for, but if for some reason it
isn't what you expected, please request a clarification.
I believe that in your case, a definitive answer *can* be found. There
are, indeed, cases where you can't track down whether or not a work is
still covered by copyright, but those instances don't apply here.
A book published in 1951 in the United States would be in public
domain today...*unless* the copyright was renewed.
("Public Domain" means that anyone can reprint the book without asking
for permission or paying any fees.)
Therefore, what you need to look for is not the original 1951
copyright claim (which, due to laws at the time, might not be on
file), but the *renewal.*
A book published in 1951 had automatic coverage for 28 years (When
Works Pass Into Public Domain: http://www.unc.edu/~unclng/public-d.htm
), and then would need to be renewed or it would fall into public
domain. That means a renewal would have been made in 1978 or 1979.
Fortunately for you, the U.S. Copyright Office has all copyright files
from 1978 forward listed on their website. Therefore, the information
you seek should be available through a simple online search.
1. Go to the Search page: http://www.copyright.gov/records/cohm.html .
Fill out the search information (usually title or author is all that's
needed) and click "Search."
2. A list of authors and titles will appear. Check any results that
may be what you're looking for and click "Full Record Display."
3. Read the results, making sure to check all data, so that you don't
confuse titles or authors. The record will show when the copyright was
4. If you do not find the book in these records, the book is in public
domain. Remember, only works renewed before 1978 (or works that are
too new to have gotten into the computer system) are not listed
FOR YOUR INFORMATION: OTHER SEARCHES
1. Previous to 1978, the Copyright Office made the same sort of
information that's currently available online available through
catalogs. Many libraries still have these catalogs, and often the
Research Librarian will check these records for you. (Or you can visit
the library in person and do the research yourself.)
2. You may also conduct a search at the Office itself. The Copyright
Office is located in the Library of Congress James Madison Memorial
Building, 101 Independence Avenue SE, Washington, DC 20559-6000. Most
records are open to public searches from 8:30 am to 5:00 pm, eastern
time, Monday through Friday, except federal holidays.
3. The Copyright Office staff can also do a search for you...for a fee.
For further information, please read "How to Investigate the Copyright
Status of a Work" at http://www.copyright.gov/circs/circ22.html
REPRINTING THE BOOK
If you do discover that the book is no longer protected by copyright
(and therefore is in the public domain), you may do whatever you wish
with it...including reprinting the book in its entirety, in portion,
or with updates.
Researcher's personal knowledge
Search of U.S. Copyright Office website