This is the classic catch-22. You were dragged into Court, let's say, because you couldn't pay your child support. Maybe the Judge has told you, "Come back in 30 days ... I order you to return to Court ... bring $1800 or I'll put you in jail."
If you don't have money for child support, how can you afford a lawyer?
If you're served with a motion that asks the Judge to put you in jail (be sure to read the pleading that's served on you!), and you can't afford a lawyer, you will be told (by the Judge -- he has to do this -- it's the law) that you have the right to have an attorney appointed for you. You WILL be asked questions about your assets and earnings, so that they can make sure that you're really indigent (the Judge doesn't want to appoint an attorney for someone who has $50,000 in the bank). If you qualify ... take the free lawyer.
NOTE: You are NOT entitled to a Court-appointed lawyer in a paternity case.
Remember that in response to a Motion for Enforcement that's filed against you, you can (usually) file a Motion to Modify Child Support and ask that the monthly amount be lowered, based on your decreased income. Modification of child support is covered by sections 156.401 et seq. of the Family Code.
When you go to Court (and represent yourself), you may find yourself sitting at a table with the AG and the Mom to "negotiate." Remember that you don't have to talk to ANYBODY (except the Judge, in open Court ... and technically, since a Motion for Enforcement is quasi-criminal in nature, you have the right to remain silent), and you certainly don't have to agree to ANYTHING. If the AG makes an offer that you don't like, or it doesn't pass the "smell" test, just say NO. Your case will then be heard by the IV-D Master (after you've sat around for another hour or so), who will make a ruling based on the evidence.
But if you stand up in front of the Judge and represent yourself at a hearing, the Judge won't cut you any slack -- all of the same rules that apply to the lawyers (hearsay objections, rules of admissibility of evidence, rules of procedure) apply to you also. And the AG will be represented by a card-carrying licensed lawyer ... who knows the Judge very well.
Throughout the process, the whole time that you're at the Courthouse for your hearing, the AG people will act as if they're in charge. They're not. They are litigants, just like you, and they have to follow the law and all of the rules of civil procedure. The IV-D Court may have been specially created for their cases, but it's not "their" Court. You're entitled to due process.