The farmer's market that started it all for me. I was not a regular farmer's market goer until my roommate took me to this one, very close to our house. Saturday mornings is now a huge ordeal in our household as we always have a hard time deciding on what to purchase that Saturday.
McClendon's is the main produce supplier at this market and they have a nice variety of produce to select from. Most notably for me, is their mushroom selection: Oyster mushrooms, shitake mushrooms, and the portabellas. We usually get all three in one fell swoop. Their oyster mushrooms are very reasonably priced for the great quality. My roommate and I are kind of obsessed with those mushrooms.
Another favorite it the Country Boy stand. I don't buy from him often but when I do it's because I finally got there early enough to snag some of his biscuits and gravy. He usually sells out of them within 30 minutes of being open! They are the best you'll ever have in AZ!!
The homemade pasta lady has some great flavor combos. Try the onion and beet flavor, you won't regret it!
The Rocking R Farms has the best beef and meat products in the biz. Last year I bought bacon from them and it was probably the nicest and best bacon I've ever had the pleasure of eating. They recently just released a new type of beef called Beefalo. My roommate and I purchased it together and made mini sliders out of it, pure awesomeness. It's a little sweeter than your average beef and very hearty. Plus the staff is always friendly.
Pickled Perfection does the pickling right, go check them out too! Lately, I've been on a breakfast burrito kick and there's no better place to grab them other than the Tamale Lady. The tamales are killer too!
I could go on and on about all the different vendors that provide fresh food and samples right on the spot but it's really a place you need to go check out for yourself!