I'm currently reading Murderers' Row by Donald Hamilton, book 5 in his Matt Helm series. The series is, sadly, long out of print, and my copy is a vintage paperback from 1962, complete with cheesy illustrated cover and a retail price of 40 cents.
One of the great joys I experience when I go to a used bookstore is pawing through the vintage paperbacks. Depending on the store, the vintage ones are mixed in with the ordinary used books, but at the store where I bought Murderers' Row, most of the vintage paperbacks were tucked off in a little hallway (the bookstore, Bart's Books in Ojai, is converted from an old house).
I'm used to the sideways head-tilt needed to scan the shelves, but these books were at the end of a hallway so narrow and dim that I had to pull the books off the shelf to get a look at them. The protective plastic they were wrapped in made a quick scan of titles impossible, and some shelves were so high that I had to ask a bookstore employee for a stepladder. Then came the task of going through all the paperbacks, looking for hidden treasure. Had to take it one by one, my hands getting dustier and dustier, because the order of the books was only somewhat alphabetical.
(Not to be a book snob, but I think was a"men from the boys" level of effort.)
You find all sorts of oddities in vintage paperbacks. Everything from delightfully (and probably deservedly) obscure trash to classics marketed in strange ways. I was on a quest specifically for Matt Helm books, as I adore the series (do not be misled by the Dean Martin movie adaptations; the books are gritty, grim secret agent fare), and the books are not easy to find.
Perseverance paid off. I was dusty and filthy-handed, and had a copy of Murderers' Row. Yes, I could have gotten it online, for less effort and possibly less money. But there's something about the vintage paperback treasure hunt that's so sweet.