Two documents, and it is worth reading them in this order if you have not decided yet.
The problem it solves, what it looks like in a channel, and, as honestly as we can put it, the reasons you might not want it. Read this if you are still deciding.
The five minutes it takes to go from an empty server to a working market, plus what to do when something looks wrong. Read this once you have decided.
The Stally Discord is where questions get answered and where every release is announced. If Stally does not support your game, your language, or the sign-up roles your guild actually uses, that is the place to say so. All three were built to be added.