I received a collection notice from Afni Inc. that looks very suspicious. It is for an old Bell Atlantic (now Verizon) bill I supposedly never paid. For those of you who wish to dispute bogus collection claims, this website is very helpful. It refers to the Fair Debt Collection Practices Act (FDCPA) and explains how to dispute a claim. I would advise, even if you think a collection is valid, to dispute it anyway. These collection companies operate in a very murky way and they need to be pressured to operate in a more honest and transparent manner.
http://www.expertlaw.com/library/consumer/fair_debt_collection.html

In short, the website advises you to submit a letter disputing a claim within 30 days of receiving the notice. They have a form letter online that you can use. From that point forward, they can only contact you once, in writing, providing documentation proving the claim, and what, if any, action they intend to take.

I referred back to the original source documents on the FTC website and the website's guidance looks to be wholly accurate and appropriate.