Like Philana and Mercury, I wrote to the address in the People's Almanac back in 1976. Best investment in a stamp I've ever made.
I bought it in paperback in 1976 and mailed off to (then) editor Nightowl for more info on NPL. I joined immediately along with a friend (Lionheart) who only lasted one year or so (but he went on to win a potful of money on Jeopardy!)
Source: npl-folk email from Oak.
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