Child Support Non-Payment?

How long do I need to wait before I report my X for non-payment? He is a well-educated man that has been out of work drawing unemployment BY CHOICE! He has a Master's in Civil Engineering and is MCSE/MCNP certified (I paid for those courses and tests) and can find a job, but chooses to stay at home and do online stock trading which I'm MORE than positive he's not told them about. He found out about my husband going out on Workman's Comp (60% pay) and his upcoming back surgery (funfunfun) and decided he wants to take me back to court to fix it to where the support is alot less or stopped because he wants to go back to school to get his Doctorate. He has stopped payments as of 2 weeks ago so he can afford an attorney...so who knows how long it will be. I'm do not want to wait around and I have no sympathy for the man, so I need to know how long I am required to wait because I'm tired of his garbage. His kids shouldn't have to suffer because of his selfishness!