Do it yourself
The hosting co for the site should be able to take care of that:
Type in the website url at sites such:
www.samspade.org
(first field then click on "DO STUFF")
This will among other things provide you with the email address for the hosting co. ( and IP for the offending website ) under these fields:
NS1-Hostname: ns1.Hostingco.com
NS1-Netaddress: 209.171.58.42
NS2-Hostname: ns2.Hostingco.com
NS2-Netaddress: 209.151.58.42
Go to the hosting co 's website & review their TOS: ( Terms of Use )
Then send an email to their abuse dept.