Located in the center of Portsmaw the Esplanade is the heart of commerce in the town. Vendors can be found hawking their goods at all hours, though the ones that work at night tend to be less reputable.
Most items listed in the Swords and Wizardy Light document can be attained easily at the market. The only exception is plate armor which has to be ordered and crafted. Luckily for those wanting such strong armor, Oscar's has a permanent stall on the Esplanade and can take orders for such armor. In addition to this equipment various odds, ends, and household items can be found for sale, as well as local foodstuffs (especially bass and catfish from the river).
One item prized by natives that cannot be found in the market is shine. The potent liquor has been outlawed by the kingdom because the natives of the region refuse to pay taxes on it. At least that's what the nobles of Willsburg proclaim. Lucky for those wishing to taste the white lightning, some freedom loving locals have become bootleggers.
I have created a bootlegger class that I'll unveil on Swords & Wizardry Appreciation Day.
More information of the Portsmaw setting can be found here.