Juchitán Zapotec is spoken in the Isthmus of Tehuantepec in the southern part of the Mexican state of Oaxaca. It has also been known as Isthmus Zapotec (ZAI) in the literature. It is a member of the Zapotecan branch of the Otomanguean language family. Like other languages in this family, it is tonal and head-initial.
Those interested in learning to speak Juchitán Zapotec can check out the course I created on Memrise. The course is a work in progress. There exist an SIL-published grammar and vocabulary of the language, both available for download.
My corpus of Juchitán Zapotec recordings and texts is available from the Jacobs Research Funds Collections, University of Washington Libraries.