You want a part(s) answer? **BG**
Assume (as the spam is that kind of spam) we are talking e-mail.
1) If you send e-mails to anyone you don't know you can not be sure.
2) if they insist on an e-mail addres for registration I may admit to being billgates@hotmail.com or --- (for 1 & 2) the ruse using the power of my domain name and tell them I am spamatyourperil@(domain) or pinnacle@ for that website or digitrad@ for here. At least you know how they got your name and who to berate (AND I ALWAYS DO)
3) Always have my Outbox visible when receiving e-mail so that any HTML (pictures &/or colours) is unlikely to fetch pictures and thus alert (by the combination of pics) who I am and if I have hseen it. That way I look like an autospamificator.
So how do I read my e-mail? Switch off the modem (unplug telephone connection) then look at e-mails and leave request the to re-connect in the background - there are usually a lot stacked.
eventually (trust me) the big players are constantly monitoring so they take you off lists as unviable. The small players may be big players trying to fool you so I will never relax the policy.
The trick is never to give them evidence you exist, which includes ignoring Nigerian surplus budgeteers & the virus hits in case it is really a trick but not the one you thought.
My last Klez32 can only have come from a deliberate attempt to hit me or get me to react - that incarnation of my e-mail address had never been used but is on a PC board help site.