They Called telling me I owed them 599.99

I got a few phone calls from this company saying I owed them 599.99 and I didn't know what they were talking about.  They said I signed up with them and never canceled so I owed them this amount.  After talking to them I still was thinking I never even heard of them how did I sign up.   After a few phone calls, they played a recording of a small part of the conversation that did say I agreed to this. I knew I had never agreed to their advertising. I want to stop being harassed by Public Yellow pages, they recently sent me a bill for the 599.99.  I do not plan on paying this bill.