What can I do if my wife refuses to let me see my kids?

I left the house since the lease is under her name as she claims and for my children's sake since I don't want to have them go through the yelling and arguments. Now when I called her to let me see my children, she refused and said she will call the police and report harassment. We are not divorced yet and she refused to sign a separation agreement. I am in New York now and have to wait one year to file for divorce. I miss my children, what should be my first step? She refused to share their SSNs, refused to provide me a copy of their Birth Certificates, what can I do?