Wanted to play Quake 3 on Linux, and got it on Steam like it says here http://ioquake3.org/get-it/ However Steam’s version doesn’t come with a CD key, a manual or a Linux copy. I can prove that I own it if necessary. What can I do? (I’m a Linux noob.)
Check your steam directory at ‘Program Files (x86)/Steam/steamapps/common/’ and look for Quake 3. There should be a q3key file somewhere with the cd key. That said, why do you need the cdkey? You just need the art assets provided in the pak*.pk3 files, iirc.
you do need a Steam key for connecting to baseq3 servers. Getting all of that data from steam when you’re under Linux can be a chore if you don’t have access to a Windows machine 
I have W7 but I vastly prefer Linux. Please give me steps to play it on Linux without dealing with Windows or Steam again.
I looked around the Quake 3 files but could not find a q3key. Also the ioquake3 site mentions some CD key check several times.
Try the following:
a. Try right clicking the game in the steam client and look for a ‘view cd key’
or
b. Go to “C:\Program Files (x86)\Steam\steamapps\common\Quake 3 Arena\baseq3” and look for the ‘q3key’ file there. It won’t have an extension, fyi.
I found it! Baffles me how I missed it lol. By the way once I use the code on ioquake3 will I be able to use it again on Steam?
Yes, you should still be able to use the code in Steam, although I don’t believe you’ll ever be asked to input it.