Holis,
Do what I do if you do not get a response from webmasters who are all too content to steal your hard work. Phone them up if you can get their phone number. This usually does the trick!
If their phone number isn’t listed in their whois record and the whois record is incomplete or wrong, file a invalid whois report with ICANN – They do take action.
Failing that, file a DMCA report against the site in question and/or take legal action.