I've got a copy of Psychonauts for the pc - I can't find my cd key though.

Please note, I'm not interested in getting any cd key other than my own - I just can't find the thing! Can someone who knows please tell me what it was on? Was it on a slip of paper? A card? I can't find it on the front or back cover of the manual, or on any of the cd sleeves. My wife installed the game originally, and can't remember what it was on.

Just trying to see if I can activate it on Steam or not :)

There is no CD-key protection for Psychonauts.

But what do you mean by "activating it on Steam"? Steam is an online store to purchase and download games, and seeing as you already own the physical copy of the game, what did you intend to do?

With Steam, you can activate a game that you already own on CD or DVD using the product key. Without a product key, we would have to repurchase Psychonauts. I would like to do this too rather than repurchase Psychonauts or have to re-install it from the 5 CDs...