Curt, I flew from Portland on Mexicana. And as to crime drug wars and safety, you leave those problems in the US when you go to Mexico. The worst thing you have to put up with in Oaxaca is beautiful children trying to sell you wooden toys or cookies. Well.. and their parents or grandmother trying to sell you stuff on the streets as well. But it is all friendly and you should buy some of the stuff from them as they are living on very little. There is a really great market some bus ride away but I can't remember the name of the market though I am sure Sandy knows. It is around an ancient church yard and there are endless stalls of everything from hats to live turkeys to buy.
Everyone drinks bottled water there and there is plenty available in the shops. My spouse and I are vegetarian so I can't vouch for the meats but the other foods in the restaurants are great flavored with 20some different kinds of peppers. Look for bowls of Pozole!! And the fresh fruit available in stalls on the street. And if you get out before dawn there are people pushing carts that will sell you cafe con leche which turns out to be Nescafe made with steaming milk and sugar. It gets you going. I never even saw so much as an argument there, much less violence.
Dennis
The major market is called the "Mercado de Abastos" and it is located in the south of the city, and you can pretty much buy everything there, from food stuff to live goats to major appliances. There is another large marget located just a few blocks south of the Zocalo, and I suspect this is the one you are thinking about.
You never drink the water from the taps. In fact, i don't even brush my teeth with it.
The people are generally very friendly and the center of the city is quite safe, even late in the evening. I would not venture too far south of the Zocalo, however, in the late evenings as the area where drugs and prostitution are to be found.
If you look at my gallery at
http://www.alternativephotography.com/artists/sandy_king.html you will see a lot of images made from negatives taken in Oaxaca city. Although I work mostly in monochrome the city is so colorful that you might want to consider color even if you primarily like B&W.
Best time to go to Oaxaca, IMO, is late October through the end of February. The climate is dry at this time, and the temperature cool but rarely cold. Oaxaca is at about 5000 feet elevation so even though it is very far south the climate is temperate all year. The summer is the rainy season.
Sandy King
Ain't it great to be an American these days?