What do I need to do to obtain a title transfer?

My grandfather passed way in 2005. My grandmother passed away prior to him. He was remarried. My grandfather and grandmother has 2 children together my uncle whom passed away prior to him and my mother whom passed away a few months ago. My grandfather had 2 grandchildren my brother whom is disabled from birth and my self. I received a letter recently regarding taxes owed on property my grandfather purchased with my grandmother prior to her passing away. I am unable to contact his wife. I am not sure if she has passed away as well. I am seeking guidance on obtaining the property. I could not find a record of probate in Travis county where he resided and passed away.