ask the taxi drivers.
when i went to puerto vallarta i ran out of weed.
i couldnt enjoy paradise with no bud.i asked local kids and old mens ladies
anyone i seen.everyone just ignored me.
then i got a taxi.
i told him i need some bud i dont drink.
he took me to a spot got my cash 20 bux
and brought me back a sack.
be sure if your in mexico to stress that you want "sin semilla"