A re-post, because its still pertinent info :)

One of the most frequent questions I have received from new patrons is "what should I wear to Zumba?" Good question- here is your answer:
Whatever regular workout attire you feel most comfortable in! Something that is easy to move in, and something that allows for adequate ventilation and body breathing. It will be different for everybody, just be sure that it is supportive in the necessary areas (ladies you know what I mean)!
Shoes need to be supportive tennis shoes. However, there is a lot of cross lateral movement in Zumba, and you may find that older shoes with worn down traction are best- so long as they still have good support.
If you are looking to make a new investment for Zumba shoes- any jazz or dance tennis shoe would be your best option. I wear Nike's dance shoe, that has a pivot in the toe, for easier turning and torquing. They run anywhere from $98- $130, depending on where you buy. I just found them on Zappos for $98.10.