Nat Pagle's Guide to Extreme Anglin' is an item that can be looted by dead players in the battleground Alterac Valley. This has been in game since the release of the battleground, but up until Legion it has not had any uses. Now however, this is part of one of the Paladin Artifact skins, so a lot of paladins will be willing to spend a lot of gold to get their hands on one! On some servers, the price of this item is 50 000+ gold, and these can actually be farmed pretty easy if you run around and loot all the enemy player corpses in Alterac Valley.
So in order to make money with this method, just queue up for Alterac Valley and loot as many bodies as you can, and you will get one after a short while. Once you get one, wait until the battleground is finished (or keep farming for more) and post them on the Auction House for a very nice profit!