Well it's just like shopping at a market anywhere except that in most markets where I'm from it's the same price for everyone regardless of the colour of their skin
Asian Geekette is right, they do sometimes charge you more if you're Caucasian and for that reason, I don't go any more - I'd rather pay a bit more and know that at least I'm paying the same price as everyone else!
But if you want to go, just walk around and have a look at the produce - don't feel that you have to shop at a stall just because the owner sees you looking and says 'yes yes' in an impatient voice - take your time. Don't wear shoes with bad grip as the floor can be slippy (especially in the fish section) and don't get upset by them rolling their eyes in mock despair because you're only buying 6 tomatoes and not enough to feed a family of 20 for 6 weeks
