Here's a site that can help get you started: http://www.nycourts.gov/ip/matrimonial-matters/forms.shtml
However, you should really speak to an attorney on this. You mention that your husband abandoned "us"; I take that to meant that there are children involved. If this is the case you really should see a lawyer. If money is an issue contact legal aid to see if they can help you or at least provide you with the name of someone who might take your case "pro bono"; that means to volunteer to help you for free. Also, law schools run legal clinics that take these kinds of cases. See if there is one nearby to where you live.