Buy Garry's mod 10 off of steam.
Garry's Mod 10
technically yes, there were a few updates it is still called Garrys mod 10 though
10$ through Steam
gmod is 10$ at garrysmod.com
10 is better, $10 Steam
yes
Off of Steam (10$) (http://store.steampowered.com/)
You can get Garry's Mod 9 for free, yes. But Garry's Mod 10, (11), you have to pay for. But Garry's Mod 10 is really worth it, in my opinion.
no because garrys mod requires that you have a game that uses the source engine
Garry's Mod has now updated and includes all features of 13 Beta
Garry's mod tornado