I find my self on Google. Then I do a WHOIS, and I send e-mails to the Registrant, the web host and to the Domain Registrar.
My favorite is when some dumbass hosts on AWS (Amazon Web Services). The infringing site then lists free downloads of my eBooks. Thing is: the ISBNs for my eBooks are owned by Amazon! The whole site gets nuked within days.
After getting some kind of takedown from the infringing site, I use my
https://www.google.com/webmasters/tools/removals to get their junk site out of Google search cache. You have to do that yourself, from your webmasters tools account, on your side.