How can we find who owns an old book's copyright? How can we find who owns an old book's copyright today, especially if the publishing company who printed said book no longer exists? This would also apply for other (non-book) publications.
Columbia University Libraries has a helpful document that provides guidance on determining the copyright status of books published in the United States. The guide provides links to online resources to allow you to determine the copyright holder. 


  Researching the Copyright Status of a Book: Protected or Public
  Domain?  
  
  A project of the Copyright Advisory Office Columbia University Libraries
  Kenneth D. Crews, Director
  
  www.copyright.columbia.edu