I'd like to know too, so (since I am American) I slogged through a few sites, including copyright.gov

Then I did what we all do, turned to wikipedia for something a person can understand. Since this is a traditional music site, I found the following to be helpful. Since I already some stuff about copyright, I think it is accurate.

"All copyrightable works published in the United States before 1923 are in the public domain;[40] works created before 1978 but not published until recently may be protected until 2047.[41] For works that received their copyright before 1978, a renewal had to be filed in the work's 28th year with the Library of Congress Copyright Office for its term of protection to be extended. The need for renewal was eliminated by the Copyright Renewal Act of 1992, but works that had already entered the public domain by non-renewal did not regain copyright protection. Therefore, works published before 1964 that were not renewed are in the public domain. With rare exception (such as very old works first published after 2002), no additional copyrights will expire (thus entering the public domain) until at least 2019 due to changes in the applicable laws."

Now out of all that the most helpful part is probably the first sentence. And perhaps this one: "Therefore, works published before 1964 that were not renewed are in the public domain."

Then I researched the old song "They Didn't Believe Me" as a test of the copyright.gov site. I brought up the record, and the copyright office says it was copyrighted 1984. (ha!) Then I looked for the song on the Lester Levy site, and it was written in 1914. It was published in the US before 1923 and is public domain.

The 1984 claim that I saw is probably one of the "usual scams" that Richard talked about. If I wanted to record "They Didn't Believe Me," I would jolly well go ahead and do it.
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