The Cuernavaca Mercado (market) is a sprawling thing that winds around and up and down. Very easy to get lost in. It's located in an arroyo just about 6 blocks east of downtown and the plaza. Much of it seems under ground with many alleys that bring you up to city streets. Just about everything is for sale but mostly divided into sections of flower sellers, meat, vegetable, herbs, clothes and music CD's. You might even see a small boy run by with a pigs head.
When I was taking Spanish classes at Encuentros I also took some evening cooking lessons. Most of our assignments included a shopping list 'in Spanish' and we were to shop at the central market before class. You'd be surprised at how many flavors of 'mole' there are. We had some very good meals those evenings.
I recently heard much of the market was damaged by fire this year. YouTube Video of the fire
Women in the vegetable section