How to find the beneficiary of probate

[Brandt Tingen]

I have come across a house where the owner had passed and the heirs are looking to sell. One of the heirs is in jail, and one is mentally challenged. I have heard from neighbors that the aunt is the beneficiary and in charge of all of the matters of the probate. This is my first time tracking down a probate sale so my questions are how do I find the attorney handling the probate? How do I find out who has the power to sell? Any special contingencies to include in a P&S contract for probate? Thanks.