Non-residential parents who Slip thru the Cracks!

Child support enforcement is an issue that has been on the forefront for a while. An issue that I seem to have a problem with is the fact that when the "non-residential" parent cannot be found there is nothing else to be done about it. I feel that if there is no way that the other parent can get in contact or find the lost parent, it is unfair that they aren't offered any assistance. What I mean is assistance in trying to locate these people. At least there can be tips offered in trying to locate them, how do they find criminals or track deviants of the law? I think there should be a program to help mothers and fathers find these who slip through the cracks in trying to avoid child support. It seems like something horrible to be done, but trust it does happen. What do you think should be done about this?