I'm in the same boat, I got a mark on my credit report and I protested it. A few weeks later I got a letter in the mail from RJM Acquisitions saying I owed $91 for the Literary Guild Book Club. I called them up and told the lady that I had no knowledge of this debt. I asked what SSN they had on file and she said that they didn't have one. I then asked if they would/could provide me with any and all records showing that I agreed to this charge. She basically told me that they didn't have it on hand and that she would remove the debt from their accounts and the credit agency.
I guess the moral of the story is that you can (legally) just ask them to provide rediculous amounts of information and, in general, it just won't be worth it for them to chase down the info for a little bit of $$$... and even if you do have to pay, make them work for it, you'll feel better.