are there any tell tale signs that your phone is tapped?

Answer 1

get a bug detector
I think they are pretty cheap

never talk about anything illegal on the phone
use different payphones if you suspect anything

stop doing anything illegal ASAP
if you are already worried about phone taps, you do not have the stomach to be a crook, find an honest job

Answer 2

Yes, when you set up a time to make a drug deal, and the police show up, I am willing to bet someone is listening.

Actually, the days of old where you could find out if your phone was tapped are gone. The equipment these days is very advanced. You will never know. Actually, you physical phone will not even be tapped in the sense of the word. The will monitor it from the phone company, or somewhere outside your house.

Hmm, I just heard a beep. Maybe I am telling too much with this answer.