There are traveling family circuses all around Mexico. I was in San Miguel de Allende, Mexico in April 2012, and I saw a pink Big Top set up on the outskirts of town. I strolled over in the middle of the afternoon, wandered around, and was "intercepted" by the Tiger Trainer. Without language to communicate, because my Spanish is poor and he spoke no English, he was able to understand that I wanted to photograph the circus, inside the Big Top and behind the scenes. He gave me permission and I attended the next two performances before they left San Miguel for another town or city. My husband and I were the only gringos there so it was great to see this from a completely "local" perspective.
For those traveling in Mexico, look around and also ask if the circus is in town. It is a pretty big event if they are—a great thing to watch and experience.