How do I make Gmod 9 show up on Steam?

[Baaaab7]

How do I?!?! I installed Gmod, restarted Steam, the game didn't show up, I restarted my computer, opened Gmod and Steam, went through the installation thing again, restarted Steam AGAIN, and it still didn't show up!!! HOW DO I DO IT?!?!

[Baaaab7]

And don't just come here to say "Gmod doesn't work". It does, my friend has gotten it to work without this problem, and he didn't buy it, he downloaded it and downloaded Steam.

[Cheese!]

I looked around and some other people have had the same problem. Read here. It's worth it to try this:

Originally Posted by guy from site

Install it again with your account logged in.. Make sure that you have HL2 Or a Source Game installed also. After that install gary's mod. When gary's mod is installed go into your steamapps, then source mods, then gary's mod. after that open the gameinfo .txt document. scroll down just enough til you see FileSystem and right below that there is SteamAppID... there is a long space then it has the number 220. Change that to 240 save the .txt document. Then restart steam and it will be in your list... thats what i had to do and it worked.

Try that and see if it works or not.