The settings.txt file does exist if you have the Steam version. I have the Steam version and it's in the same place as the non-Steam version.
Go your user folder and there is a hidden folder called AppData. Windows likes to hide this folder because important configuration files tend to go in there that if you mess with them things can break. If you can't see the AppData folder in your user folder you will have to enable the "Show hidden files and folders" option in Folder Options.
The full path is going to be:
Where "username" is your Windows username.
edit: fixed path
[Edited by crayo, 11/6/2009 7:26:44 PM]
[Edited by crayo, 11/6/2009 7:27:56 PM]
* Updated game trainers and cheats daily
* Get notified when new cheats are added
* Request which games get new trainers
* Priority support with any problem