Help with construction set

[ChillarN^]

Hi, maybe this is the wrong forum but I need some help.

When you install a mod with its own meshes, textures, ect files, it asks you if you want to replace the originals with these "mod" meshes.
So when I try to find something out of these original folders in the TES, I just find the mod things. For example today I was trying to create a new class but I couldn't find any class icons. So how do I find the class icons ect?

FYI, this is for oblivion and yes I'm a noob at this.

I'm eagerly awaiting the english translation of Nehrim so I can try out what looks like an awesome mod

[Dunkler Tod]

all the files from vanilla oblivion are packed into the .bsa-files in the data folder.

[ChillarN^]

and how do i open the bsa files?

[Morbide]

With BSA Commander. To get aquainted with the CS look here.