Here's a quick little review of a stand I came across at our farmer's market. The stand was Taco's El Vaquero (sic). The selections are limited but fresh and tasty. This day he had chicken, steak and goat meats for tacos or tortas. I had a goat and steak taco. Both were very good, loaded up with the works. I also tried a fabulous agua fresca that was a mix of apple, melons and banana. One of the best aguas frescas I've had in a long time. He just does farmer's markets in Northern Orange County (Orange, Fullerton, Garden Grove and Anaheim, I think) as well as catering.
You can see the phone numbers on his sign. Don't go to the address though - as I say, it is just catering and the markets. I think the address is his home.