In KotOR Tool browse to
ERFs -> TexturePacks -> swpc_tex_gui.erf
and click the "Extract Entire ERF File" to pull all the *.tpc files into a folder.
Open a command prompt in that folder.
md icons
move i*.tpc icons
This will create a folder called icons move all the tpc files that begin with I into that folder.
Next, download BulkTPC2TGA (
http://www.lucasforums.com/showthread.php?p=2272437#post2272437) utility and put it in the icons folder.
Open a command prompt in the icons folder and type:
md tga_icons
bulktpc2tga . tga_icons
You'll get a bunch of messages that say "Use of uninitialized value in pack at /PerlApp/Bioware/TPC.pm line 83." but the program is working. You should now have all your icons as .tga files in your tga_icons folder.