An abuse complaint to their web host or domain registrar would be the first place to start. infosniper.net is one place to start, any random Whois provider will turn up their registrar.
Thanks, will give that a go. There must be some way to alert google too right? It is pretty bad that they serve it up as a legitimate search result.
You would expect the real github to be recognized and any other duplicate flagged automatically as fake.