B.E.
It's never too early to introduce additional languages. It's best if they can be spoken by a native speaker. For example, if your nanny were Chinese and spoke Mandarin to your daughter, she would get the true pronunciation. The window of opportunity to speak with the authentic accent closes by age 9, before we start teaching a 2nd language in our schools. Some children experience speech delays if they are learning multiple languages, but it all gets sorted out soon enough....don't worry. This is an important ingredient of brain development, and most of us miss the opportunity.
You can look into BilingualBirdies.com, the Children's Aid Society location isn't far from Washington Sq.
Also you can find cool Latin-rhythm music for kids called Bilingual Songs CD English-Spanish, item #2332 at www.toysofdiscovery.com
If you do form a small group, you can host a party and earn free CDs, toys and books. Read about hosting a party at www.toysofdiscovery.com
Good luck!