I live in Texas in Brazoria County, I have a two year old son with my ex-fiancee who has only seen him two times in those two years. I have talked to him on and off and he says he's going to come see him but never does. I have not heard anything from him since Feb of 2008. I am not receiving any support of any kind from him nor do I want this, all I want is him not to be able to float in and out of my son's life. I filed for child support when my son was about six months old but they were NOT able to find him and still can't. He doesn't have a job, license, car, or his own place so it is very hard to track him down. He is not in my son's life and neither is any of his family. I think my biggest problem is that him and I were still together when my son was born so therefore he is on his birth certificate and has his last name. And I was also told that I can not change my son's last name to mine unless I got a court order? Is there any way that I can file abandonment papers so that I can get full custody of him? Or how do I file for full custody?

You have full custody of him. At least you have full physical custody. There doesn't appear to be any visitation ordered by court.

There is a process to go through to get his name changed without his consent. It involves several means to try to locate him. If you cannot locate him by these means, the court may issue the name change without his consent. The easiest thing would be to get him to agree to it though.