Here are some Kundalini Yoga links for the city of Oaxaca:
Centro Anahata: http://centroanahata.weebly.com/clases.html
Prashad Centro Kundalini Yoga: divicalvo@hotmail.com.mx
There is also Agama Yoga on the coast of Oaxaca in the town of Mazunte: http://www.agamayogamexico.com/
This is an old thread, but maybe this info will be helpful to someone.