Squizgar here to tell you, Matrix you're a very pathetic person. Does doing a single search never cross your weak little mind?
C:\Program Files (x86)\Adobe\Adobe Photoshop CS5.1\Plug-ins
C:\Program Files\Adobe\Adobe Photoshop CS5.1 (64 Bit)\Plug-ins
Your plugin folder IS there. If it wasn't your photoshop wouldn't function.
No you can't use GIMP to edit DTX files since there is no plugin for it.
Are you going to report me when I'm helping you? like you did last time.