You have to download Steam on your computer, then Left 4 Dead 2 can be bought from that.
Install it.
Yes, I have it on my laptop =)
only on computer i think, if you play it on the computer it is z,x, and c
4 players can play in Left 4 Dead 2.
when u play left 4 dead 2 online on computer it is powered by anti cheat servers so maybe it is the same for xbox 360
Left 4 Dead can be played on either PC or Xbox 360.
Yes, you can play left 4 dead 2 on steam if you buy from Gamestop.
Yes you can work Left 4 Dead in a PC, but you have to download it and buy the game.
Yes you can play online
One can definitely play Left 4 Dead on their own. But it is more enjoyable when other people are dying along with you. :)
which laptop?