For some reason, I had that exact problem with my second edition copy of Vampire: the Masquerade. I swear, I purchased at least five copies of that book before it stopped disappearing.
Anyways, I think I got a little side-tracked from the OP's original intention with this thread. I've found goodies in old RPG materials before, especially those donated by former gamers.
My red box copy of basic D&D included a sheaf of character sheets and dungeons drawn on graph paper with loosely keyed entries written on notebook paper. To me, that was pretty cool, trying to make sense out of a campaign played during the early eighties with twenty-year-old notes. I imagine that it must be kinda like finding a map to an unknown dungeon for a PC. Some of it was just good wonky fun that I could rib people about, like the character sheet for "Bardo the halfling" who possessed a ring of invisibility and conspicuously noted on his sheet that he liked elves and wizards.
A few years ago, I purchased the boxed set of the old Star Trek RPG published by FASA (I already owned a copy, but I took those booklets around to Star Trek conventions and got them signed, so I wanted an extra copy). That product contained the last guy's campaign notes, including descriptions of two star systems and their starship and crew. I ended up using one of the planets and the ship in a game.
Just recently, I was considering running a 4E game with an OD&D theme. I dug out my old OD&D stuff and in the Rules Cyclopedia, I found notes from my sister's campaign she tried running way back in the early nineties.
So yeah, I've found a pretty hefty amount of goodies like that in old products.
