Not sure what folders you're looking for.
I am on windows btw.
But here's my GIMP's folders
![Image](http://gimpchat.com/files/3612_my%20GIMP%20folders.jpg)
And here's my GIMP's Roaming folders
![Image](http://gimpchat.com/files/3612_my%20GIMP-roaming.jpg)
If you're looking for where the plug-ins folder is you can go to GIMP -> Edit -> Preferences and then Folders and expand that to see more.