The brokers are an enigmatic group. We know little about them, save that they can travel to many lands in the Shadowlands that we cannot. How they do this, we are not sure.
They are willing partners in trade, though, and through them we have acquired many rare and valuable resources that cannot be found elsewhere.
They hold in high regard a currency of their own creation, you may find such coins in your travels.
I will gladly take them off of your hands to bolster our supplies.