The self-service forms for Maricopa County Superior Court are available here: http://www.superiorcourt.maricopa.gov/SuperiorCourt/Self-ServiceCenter/Forms/FamilyCourt/fc_drese1.asp
You can prepare and file the forms yourself (without an attorney). Just make sure to carefully follow all the instructions on the forms. Good luck!!
The answers provided are for general information purposes only. They do not establish an attorney-client relationship and should not be construed as legal advice
If he is behind on his child support for this current tax year, he cannot claim ANY of the children. You need to file a Petition to Enforce Child Support and Spousal Support and request contempt of court. If you do decide to hire an attorney, you should request attorney's fees. Frankly, you stand a good chance to get them in a case like this. Also, in your petition you can request that he have to pay a purge order, and if he fails to do so, then sometimes a court may give him jail time until he pays off the purge. Sometimes attorneys are able to work out fee agreements that may be more affordable in your case. You should at least get direction from an attorney via a free consultation. Several firms on here, like mine, offer free consultations.
This answer is provided for general information only and is not to be construed as legal advice. This response is not intended to create an attorney-client relationship.