Re: Where can i find retro PC games ?
GOG has both Kotor games as well as the entire Jazz Jackrabbit collection. They don't have any age of empires or any sort of Tarzan game on there that I was able to find. Depending on how retro you're talking they also have stuff like every single Ultima game, I think Myth and the remastered version of it are free, almost all the old bioware and Black Isle RPGs and even going way back to stuff like the Dark Sun series and like old OLD school DnD stuff.
Others have already said myabandonware.com which comes with it's share of shadyness as you never truly know if that stuff is contaminant free (but I suppose the same could be said about this site too in theory).
I'm looking for games like Age of Empires 2 & 3, Tarzan, Star Wars KOTOR (Knights of the old republic), Jazz Jack Rabbit 2, etc.