The big gate bordering the church grounds leads you to the Tlacolula market. One of Oaxaca’s biggest and oldest, the Tlacolula’s [1] market draws tens of thousands from all over the Valley of Oaxaca [2] every Sunday.
Wander around and soak it all in—the diverse crowd of buyers and sellers, and the equally manifold galaxy of merchandise. How about a hand-hewn yoke for your oxen, or a new stone mano and metate for your kitchen? If not, perhaps some live (or ground) chapulines (grasshoppers), maybe a live turkey for dinner tomorrow, or a hunk of sugarcane to chew on while you stroll?
Links:
[1] http://www.moon.com/destinations/oaxaca/oaxaca-valley/east-textile-route/tlacolula
[2] http://www.moon.com/destinations/oaxaca/the-oaxaca-valley