Where can i find information on inheritance?

My father died in feb 2009 and grandmother shortly after. It turned out that my grandmother was a beneficiary for someone in the family that lives in ny. My uncle said that the will listed that my grandmother receives the inheritance. and if she past it goes to her kids and if any of her kids past it goes to her kids, kids. will it turns out that im my grandmothers sons daughter. ONLY daughter and he was never married. Now ? is how to i get ahold of someone in new york that has this file? Because my aunt and uncle is trying to fight me to not receive nothing. and my other uncle wont give me any other information. All I know is that the person that passed away lived in new york. and the file is with a lawyer