My ex-husband lied about income

My ex husband had a business that he and his father owned. He made 60,000/year. He showed himself as an employee and had his dad sign off showing he made 8.00/hour and only had to pay 55/wk for our daughter who is now 15. I had the medical insurance through work and he was ordered to pay the difference. He hasn't paid a few thousand dollars in med bills and hasn't paid child support for the last eight months. Our daughter is a problem child and has had problems in school. This year she decided to move to her dads to try school over there in his town. I've received 3 calls from the new school informing me that her behavior hasn't changed in the new environment.

The original agreement was for her to try school there and see if the change would help. In only 2.5 months my ex filed a court case for residual custody and 20% of my income for child support yet he has gotten away with lying about his income the entire 3 years we've been apart. Not to mention i am friends with an ex employee from there company and he informs me that they told him the lie and that his girlfriend ,now his wife , was getting his 60,000 a year salary while he makes 8.00/hr. I can't afford an attorney for a long drawn out dispute. I've played by the rules the entire time and he hasn't and now he's trying to take what little bit i got and i can't lie about. I have no problem paying for my daughter, it's just not fair that i was due $1000/mo. until they lied and i only got 220/mo. now on my salary i'll owe approx. 650/mo. and won't be able to keep my home. Not to mention he has thrown his hands up 5 times in 3 years and said i can't stand her and don't want her in my life anymore! And if he gets away with this and gets tired of it again, i won't have a home to take her back to. Any advice?