The story "Souvenir Paddles," by Dave Wallace, features a male protagonist who ends up getting more than he bargained for when he agrees to let the female store proprietor who sells him a paddle apply it atop his naked buttocks.
One of my short stories, "Search and Employ," features a spanko-dominant woman in a challenge vs. her husband, attempting to purchase 'pervertible' punitive implements at a limited price in a roadside antique store.
The formatting came out somewhat flawed so the dialogue may be difficult to follow, also it was written to a 500-word limit for a contest, therefore it's quite brief and only describes the spankings to come via verbal exchanges.
My serial "Sisterhood's Greetings" features a 'secret santa' situation in which each male spankee has to give a selected-by-drawing female spanker an implement which she doesn't already have as a Christmas present, which she will try out immediately upon his bare bottom after opening it at the party.
Who knows, perhaps I'll even get inspired and finally finish writing the concluding chapter...

--C.K.