My father passed on about three years ago, he split with my mother in 1998 and left her with me and my little brother, he was ordered by the court to pay maintenance but did not. My mother raised both my brother and I on her income and my father re married and had a baby girl with my step mom. After the funeral she disappeared , changed her number, and cut off all contact to my family. My father was an actor in his early life and moved on to be a restaurant owner. All business were closed down but still both my brother and I did not receive anything from him not a cent till today. What steps can I take and what can I do, I can't find this women and I don't know where to start.

Here is the problem. You may or may not be owed anything as far as inheiritence goes. That will depend upon state law. What state is this in?
Another thing is that your mom will be owed money from the estate if there was unpaid court ordered child support. Leaving everything to the wife does not relinquish the debt. You most likely need to hire professionals to find everything and create a paperwork trail. Your mother is the one that will have the right to collection for support owed and is first in line. She will have to be involved. If she has passed then it may be possible for you and your brother to collect on that debt. You need a private eye and a lawyer to waddle your way through all of this. Some states charge 10% on arrears so even if the amount was low years ago it may have balooned into something larger.

Find the trail and pursue it.

First you do not know there even was an estate. He had closed his business and so on. Next if things were in joint ownership with his new wife, they can often pass to her without going into an estate.

Next you have no claim to any money that was owed your mother, that is for her to claim.

You need to go to the court house where he lived when he died and even see if there was probate and an estate

And since this happened 3 years ago, there may be nothing left if there was anything in the first place. Unless you are sure there would be a substantial estate this may cost more to find him then you will ever collect.