How can I get custody back of my three kids from their father?

I never had the courts involved and I never lost custody. My very smart ex husband lied to me and told me at the time of our divorce that he hired us both a attorney. I was lied to and tricked into signing him full custody. I never thought in a million years he would do this and once I found out I've been so devastated ever since. I'm a excellent mother and all three children ages 10,8,and 8 years old all want to be with me. My only problem is that I'm low income. I was told I had to wait 2 years in the state of KY by a attorney to wait until after that 2 years before a judge would change his mind. So my waiting on the 2 years is over and my children want to be with me now more than ever and I feel the same way! He shows no stability and has enrolled them into 4 different schools and keeps moving in with different people. He's recently started not letting us talk everyday due to his current girlfriend getting jealous. He's not wanting them to visit with me now all of a sudden and is trying to make me sound bad to the children. He thinks I have no rights over how he tricked me into signing him full custody. I never signed away my rights is what another attorney told me. please help!