interest laws on arrears/and more!!

How can I find out more about the interest laws on child support arrears. If the court order is made within a state that does not charge interest on arrears, and I live in a state that does charge interest, it goes by the state I live in, not the state the order was made? I'd like to find out what states do and don't charge interest.

Also, because my ex collected welfare in WA. while living with her boyfriend for 15 years, in the state of CA where I live that makes it mandatory that I have a wage assignment. I am now paying only arrears, as one son is of age and the other is now living with my mother. Do I have to have a wage assignment for the rest of my life now? She may still claiming welfare even though my son lives here in CA.

I have had a problem in the past with an employer who with held child support from my paycheck, but it was not on the Family Support's record as being received. I was laid off two weeks after the wage assignment, and this is not the first time on a job that I have been laid off shortly after the employer receives the wage assignment notice.

I've repeatedly asked the Family Support Division (almost five months now) for an audit so I can make sure my last employer actually paid Family Support the child support they took from my paychecks!
I get no response from them.

I've been to a lawyer for a consultation, but they won't take my case for less than $2500. I can't afford an attorney. I'm trying to seek legal aid, but in the mean time, any info on this situation?