You can get them via most major torrent sites. Not sure sythe's policy on this so i'm just going to mention the abbreviation: PB/KAT.
Only download verified ones with lots of legit comments/seeders, and make sure the extensions are video formats, not .exe etc (or play them in a VM to be extra safe)
Sites like Tubeplus.is can allow you to watch GoT for free. I use it to watch The Walking Dead. They update the site with a new episode the same day it comes out, which is pretty fast!