So I can't seem to find a CD key for this game? What gives?

There's no option when I right click the game, and I don't see it on HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\CD Projekt Red\The Witcher 2 either

I know it's not the steam forums, but figured maybe someone on CDPR could enlighten me :O

Have You tried to Shift-Tab and see if it's displayed there? Steam games usually displays this during startup, and when it disappears it goes to the aforementioned Shift-Tab screen.

I got it to work, once I ran the game.

More importantly, why didn't you buy it from GOG? YOU STEAM-ACHIEVEMENT-WHORE?!

:p