This quest is acquired from Shopkeeper Suul, who can be found in the central marketplace of the city of Levant.
Suul wants you to deliver a ledger to the shopkeeper in Cierzo, named Doran. Given that Cierzo is the first town that you find yourself in, its location should be familiar to you. From Levant, head south west toward the entrance to Enmerkar Forest. Once there, travel to the north western most point in the region, and then on to Chersonese. Cierzo can be found in the north west corner of the region. Doran has his shop in the central marketplace of the town.
Once you’ve spoken to Doran and provided him with the ledger, he will reward you with a Large Emerald, which can be sold for 80 silver.