Completely deleting all addons?

Hey i have tried but i do not know how, i have not played gmod FOREVER but i kind of want a fresh start. Is there anyway to make the game as if i JUST BOUGHT IT?
Like i think i tried delete all game content but the addons where still there. I want a fresh start can anyone help? Also i need to do something for a friend so i dont have time to spell check or even really care about spelling. Atleast in this post :3

If you delete your entire garrysmod folder it’ll be re-installed from the gcf completely.

Rename the current Garrysmod folder to GarrysmodOLD(Or anything different than Garrysmod), and it will enerate a new fresh copy. Then delete the renamed folder after you start Gmod again.

I love you guys…

[editline]13th February 2011[/editline]

XD kidding but srsly ill try!