Stepsons Egg Doner Wont Pay Court Orderd Child Support

My husbands ex-girlfrind has 5 children an has custody of non of them. Up until about 5 months ago the only visitation that this woman had was every other sat. for 3 hours supervised and for the 5 years it had been like that she only saw him about 25 times total. For about 18 months no one knew where she was and we never heard from her. Which ment that we never saw a dime in child support. Up until Jan. 2010 this is how it went. She did end up taking us back to court and the judge awarded her every other sat. night overnight and that she must pay all of her back support and also the current. This worked until the trial was done and she got what she wanted and now quit her job and pays nothing. I guess I don't understand how the court system could let this happen. It is hard enough trying to raise a child in this day and age and to let these "dead beat so call parents" get what they want and still not pay. We have tried going thru child support recovery in Iowa and it seams as though nothing is being done. What does a parent have to do to make the other step up and at least pay for their child they helped to bring into this world?