If your child's father is not paying child support, the first thing to do is contact your attorney general and file for support. If he does not want to pay, or cannot pay, it may be grounds for parental right termination in your state. Your attorney general should be able to give you more information. You can also look up family law lawyers in your area... many of them will give a free first session for advice on what to do next.
Here's the link to your state's attorney general:
Arizona Attorney General, Terry Goddard
Arizona Attorney General, Terry Goddard (link to the contact page)
Peace be with you in your decision!
Jeska