Best way to get these folks off your back, state the following.  "Man!  Where were you guy's five months ago?  Ya, we're closing our doors on the first of the month, but if you are interested in buying us out, you would be a real life saver!"  

I love to keep them on the phone asking dumb questions or making stupid statements.  "I heard that your CEO is a heavy drinker, why should I trust you?"  "People say that you have a M-eth lab in your company basement and this is just a front, is that true?"  "A friend of mine told me that everyone over there obtained their college degree online, I don't feel comfortable with online degrees."

Don't take it - Give it!

Fishing for info.  Called late at night and left message.  Name was John Purillo?

Message stated "urgent and confidential" matter.

I am assistant to the owner of the company. He only takes scheduled calls and the front desk sends all calls for him to me. So I knew that the person calling was fishing. Any suggestions how to get them to stop, I really don't have the time to waste on unimportant interruptions.
As stated before the caller has a heavy East Coast accent.

This company is a "privately held" mergers and acquisitions group. Very thick East Coast accent wanted to speak with our company president.

We are not interested in merging with anyone, acquiring anyone or selling out our company.