I joined the NPL in May of 1979. I won the Second Annual American Crossword Puzzle Tournament at the Marriott Hotel in Stamford, Connecticut, on March 4, 1979, and that opened up a whole new world. WILLz invited me to join the Fairfield Puzzlers, and I think it was he who told me about the NPL and gave me a minisample.
Source: Ditto Hoozoo in January 94 Enigma.
First Issue: Jun 1979
The choosing of my nom was very simple: my name is Miriam, nickname Mimi; Mimi=me me=Ditto.