Giovanni, SpamSieve is an excellent product and does everything automatically. Saving the email addresses of spamers is nit likely to help you since rarely do people receive spam from the same email address twice.
>So when I asked for information regarding email lists, I intended these >kind of lists, where the email owners gave their permission for sharing >their personal information: You need to contact companies like this individually. They will tell you what conditions they have and what their price is. They will likely want to know what your purpose is and what products or services you have to offer. Reputable companies do not sell their lists to anybody that asks. Obviously you should be looking for companies that provide similar or complimentary services to your own. Getting any old email list from any old company won't be worth whatever you spend buying the email addresses. Steve

