Joppa (pronounced Joe-pa by Ptychomancer in his livestream) is the starting location for the game and an important area for early gameplay.
Several important characters can be located in Joppa
Argyve - can be found in his workshop, located in the southwest section of Joppa, he provides Tinker supplies and a few quests.
Mehmet - can be found to the left of the watervine patch, and provides a quest.
Elder Irudad - can be found in his large hut, dominating the northern section of Joppa, he provides some background information about Joppa and Qud.
Tam - can be found in his shop in the southeastern section of Joppa, he provides trade.
Warden Ualraig - Protector of Joppa and master of terse phrase.
Ctesiphus - Good omen and town mascot. This ray cat can be found wherever he wants to be.
Several chests in Joppa can be looted by simply closing the door: One in the house northwest of your starting position, one southeast of the Elder's house and northeast of the last house with a chest, and finally one more in the first house east of the last with a chest. Tam himself does not care if the chest in his shop is stolen from, though the door to his shop should still be closed to keep the farmers from seeing. Irudad and Argyve's chests can be stolen by cutting holes in their walls (ctrl+bump) and trading places with them until they can not see the chests, and then going and stealing from the chests.
You can get Harvestry without spending skillpoints for a few drams of water: Do water ritual with Mehmet, Warden Ualraig and Elder. Pickup your Harvestry while doing ritual with Mehmet or Elder for 75 Joppa reputation.
Everyone hates the Zealot, thus you can kill him without angering the rest of the town. He isn't all that strong and can be killed easily. He gives 25XP and drops a decent selling book.
In the north-west pool of Joppa, in the bottom right of the top-left 2x2 square of water, between the farmers, there is an alternate route to Red Rock via the Waterlogged Tunnel. Walking near it will reveal it. Press ">" to enter. Be warned, the underground route can potentially be more dangerous than the overland route.
In the north-east corner of Joppa, there is a shrine with a pool of water around it. Using look 'L' on it will give you a piece of lore, which could give you the location of your first historical site to visit along with the corresponding quest - simply visiting the historic site completes the quest for an easy 500xp even if you don't plan on exploring it.