Getting to the blacklists of ISPs and mail administrators is so unlikely for companies, especiallly those who use the web in their marketing campaign. Moreover, common email users are also affected by the blacklisting issue.
If you would like to check whether your IP address is in the blacklists, try visiting certain blacklist databases such as www.spamcop.net/bl.shtml or www.spamhaus.org/sb/. If you already know your IP address, just click the mentioned sites and proceed to the remainder of the process. If you don’t know your IP address yet, just click [start menu - run - cmd.exe], after which, type ping www.domain.com; Your IP address is contained in the brackets.
Here is a more comprehensive link for blacklist databases : http://directory.google.com/Top/Computers/Internet/Abuse/Spam/Blacklists/
