Typically when sending an email with content like that for a notification you'll "defang" the URL by rendering it like "hXXp:// foo (dot) bar (dot) com" or something along those lines to ensure that it isn't automatically flagged and filtered, though it's also common on the receiving end to apply no spam filters to their abuse@ email as well. You'll usually have better luck sending this information to the abuse email listed in the IP whois than to any contact information at the domain itself.