Please don't link to torrents of copyrighted material... Also, just a heads up, none of those were the latest... The game is updated CONSTANTLY, those were uploaded in 2009 lol. I know it said latest, and I'm sure it was the latest at one point in history, not anymore though.
1. As for your issue, I would recommend you download Steam
http://store.steampowered.com/2. Buy Garry's Mod
or work out a way to bypass Steams DRM.
You should be able to obtain the latest Garry's Mod with Steam.