Help, i dont kow how to dance! lol anyone know where i can find free dancing lessons in nyc?

my girlfriend is a big time dancer and im anti dance, i want to be able to join her in her pion, so i want to learn how to dance, she doesnt know im trying to learn cuz i want to surprise her =) she dances ballet and modern mostly, but i wana be able to feel comfortable going out and dancing with her, fast songs slow songs w.e have you, i live in the bronx so anybody know any places or sites to direct me wud b a big plus, please and thank you