This isn't actually a book... but when I scan it it pop up on Goodreads so I guess this is okay!
It's just some postcards, like the title says, but with very cool cartoon like illustrations and some very grumpy/sarcastic message. Just find those perfect if you have some dark humor like I do, not necessarily a postcard guys, but this could replace like birthday cards of stuff like that with a good touch of humor. Very simple but funny!