One completed book I'm keeping is Henry's "$10,000 Trivia Challenge," which is basically an NPL con extravaganza in a book. Al DeSuda won the actual contest.
Correspondence tucked into Stanley Newman's "Ultimate Crossword Book" indicates that I was asked to - but never did - write a piece for the section by solvers. Apparently I wasn't always a media whore.
I did some of the crosswords in a Maleska book of quotation puzzles, and was surprised how non-bad they were, and how smoothly I was solving. Then I saw I also have a (mostly solved) compilation book that includes the book I was doing, so I must have subconsciously remembered them. Still, it's been a while. And now I won't redo the known duplicates that haven't yet been solved.
After taxes, I'll also enter my reference books and piano music (though most of that is pre-ISBN).
I still haven't found that first volume of ACPT puzzles.