Former Business Partner Owed Me Money & Not Paying

[brap]

What is the name of your state (only U.S. law)? Virginia/Maryland

First off, I hope this is the right forum, I apologize if it is not. Me and a former business partner formed a company last year. In January 2008 I left the company, signing over my shares of the company to him. We had an agreement made up by the corporate lawyer that divided the corporate debt.

The problem was that the amount he was to pay was for a credit card is in the company name, but I am the guarentor for, so I have him send me the money and I make the payment since I am ultimately responsible for the debt.

He had been paying on time until last month when he stopped returning emails. After numerous attempts at calling, emailing, and going to his house to collect September's payment he sent me an email saying that the company was in financial trouble and may be filing bankruptcy. There is still about 19k he owes. I paid Septembers payment out of my own pocket, and it appears this months payment will be paid by me too since he is still ignoring me.

Again, I do have an agreement drafted by the corporate lawyer that states the amount of debt he owes.

What can I do to collect this debt? I'm assuming I'll need to seek out my own lawyer, but before I spend money on one I wanted to check here to see if the fact that he may be filing bankruptcy negates the contract and the debt he owes.

Thank You