You have to download Steam on your computer, then Left 4 Dead 2 can be bought from that.
If you mean the CD key,buy your own on Ebay,or buy the game at amazon or your local computer/gaming retail.
buy a copy!
Install it.
On the back of the game manual/CD case, or on your Steam account.
Yes, I have it on my laptop =)
Left 4 Dead is available for Mac OS X, Xbox 360, and Microsoft Windows.
only on computer i think, if you play it on the computer it is z,x, and c
If you are using the Xbox then unfortunately no, but for the computer there is the developers console.
For the PC and Xbox 360
No, Left 4 Dead 3 is not coming out. There is only Left 4 Dead and Left 4 Dead 2. Both fun games.
The Valve store is a gaming store where you can buy computer games. Such games that can be bought on Valves are ones such as Left 4 Dead and Left 4 Dead 2.