collection agency keeps harassing me about a debt I don't believe I owe. What can I do? Send them a certified letter asking that they verify the debt. (Sample letters are included in our debt kit.) Verifying the debt requires that they send you copies of documented proof that you owe the debt. There is a statutory period governing them, so you need to act as quickly as possible after that make initial contact with you. You can also ask them to stop contacting you since you don't believe you owe the debt. Once you have told them this, they are barred under the Fair Debt Collection Practices Act from contacting you to try and collect the debt or putting negative information on your credit report. They can contact you to tell you they're giving up all collection activity or they're going to sue you.
http://www.bcsalliance.com/y_debtFAQ.html