Forged Will

My grandfather passed away in 1999.He didn't leave a will.And as he had two sons.so the property was divided between them equally.But it has come to our notice this year that there was a will of which we were not aware and not even notified by any authority. According to that will some part of agriculture land that my grandfather had was named to my uncle.We never had any idea regarding such situation and it came to our notice only when we demanded our share in said property. Now there is an unregistered will(as told by the patwari)...of which we were not aware.I am having a hard time obtaining the copy of said will(my uncle holds a strong clout in the local tehsil).How can I obtain the copy? Secondly,we have an old piece of paper which was written by my uncle on how the property should be partioned after my grandfathers death(sort of a will)..he wanted my grandfather to sign it,to which my grandfather refused. Thirdly,my grandfather was illiterate. He used to thumb impression for transaction but few years before his death my uncle had taught him to sign his name under the impression that using sign would save him time in banking transaction. my uncle himself used to sign certain document in my grandfathers name. Respected members,please help..