Oaxacaphiles will cringe or love that Seth Kugel has written a Frugal Traveler story in the New York Times travel section about this lovely, small village outside Oaxaca city. Enjoy! Article comes complete with map and a video.
Personally, not many but the most adventurous would undertake this type of travel. There has been a discussion on the comments section of this article about the personal safety of going in to an unknown village and presenting oneself. Most advice is to be cautious and to know the territory. The Tlacalula Valley people, where Seth explored San Juan Teitipac, are usually friendly, warm and welcoming to visitors. We did not find this to be the case in San Mateo del Mar on the Isthmus of Tehuantepec. It was very easy to read the glaring eyes.
There is also an issue of safety in the Mixtec regions of the Oaxaca highlands where remote villages have been in an indigenous human rights struggle with a repressive central government. It is too easy to get caught in the middle.
So, as always, use your judgment!