My question involves child support in the State of: Illinois

My ex is a few months behind in child support for our child (give or take about $1,000). He is getting unemployment and a small amount from the military every month but he is not sending his child support in from that money. So I am going to take him back to court.

Is there any way I can not file a Petition? Is there something else that does not requrie a Sheriff to serve him, like something I can mail? He lives over 150 miles away and I have drive there and give the Sheriff department the papers to serve him and I really dont have the extra money to do that.

He also is $4,500 behind on another child support case for his other ex and their son.
Is there any way I can use his other court issues to my advantage?