Help! Being Sued by CACH on behalf of MBNA, What next?

[seriously screwed]

I have an old MBNA debt that last payment made was 12/04. TX SOL is 4 years so that doesn't help me at all. Was served with Citation and Petition today (11/13/06). I have 20 days blah blah blah to respond in writing.

1) What form do I use to respond and what do I put in it and who do I send it to?

2) Should I file a request for discovery? if so, how?

They provided the NAF award letter showing that I owe MBNA $8000+. I did get some letters from NAF, but thought it was junk mail and ignored. My thoughts after reading these other posts is to:

1) Answer cititation within time frame.

2) File a motion to dismiss for lack of evidence (to make them come up with the original agreement and proof of how much I owe them etc.

3) Request a notarized certified copy of the Binding Arbitration agreement that binds me to an arbitation with thier client. (Part of the award letter states that I agreed to arbitration in my cardholder agreement, I figure they should have to prove that)

4) Request original signed contract stating we will owe the CA when they purchase the debt from the OC. (To see if we are legally bound to pay them. In the Petition it states: Defendant's defaulted indebtedness was purchased for valuable consideration from OC by the mover, CACH,LLC.)

5) File a request for production of documents/discovery. (see if they can prove how much I owe, and the contract as the amount is quite a bit higher than my high balance listed on my credit report.)

I don't know which of (or all of) these I should do, much less how to do them. Any help is greatly appreciated.