According to The Register of Known Spam Operations (ROKSO) 90% of all
the spam received in the USA and Europe can be traced back to 200 groups
with 500-600 individuals doing large scale spamming.
Spam emails are often sent through email servers that are miss configured
or allow any sender to relay messages through that server. This way it
gets harder to track down the spammer, but not impossible. It is just
a matter of time till the spammer get the accounts he is using canceled.
Spammers often conceal himself to operate in other countries. They also
pretend that they are small network operators and that the spamming is
actually from their customers.
The spammer people move from ISP (Internet Service Provider) to ISP as
they get caught. When banned from one they have several other accounts
going. It is mostly a cat and mouse game.
Most ISP have strict rules against spamming activities. Never the less
ISPs can not know in advance that a customer is going to do spamming through
Canceling the accounts the spammer is using do not result in spam stopping.
The spammer will never get banned by all ISPs. The only way to permanently
stop spam is to get the spammer in jail, and deny them access to network