Anything and everything, in jaw droppping volume, themed in whole streets at a time...
having escaped the baby clothes avenue i got stuck in nail varnish boulevard for at least an hour, finally selecting some orange sparkly stuff (which i still have and love!) before exploring further wonders of market land. Also great food stalls, cafes and restaurants along many routes, this is where you will find ordinary people buying their (extra) ordinary stuff!
There are many markets in the city and obviously no contact number, but head to the area around the government buildings and square, and follow the sound in the streets...
Updates
The main market one should visit is the Mercado de lo Sonora, otherwise known as "La Merced". It is the biggest outdoor mercado in Mexico. On weekends in Santa Clara in Ecatepec there are great "Tianguis"/markets. If you have the time, visit Chiconcuac on a weekend, a town outside the city near the pyramids. They sell a lot of wool sweaters, etc.
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