They are no longer installed with CS4. They are dead. They are included on the CD in the goodies folder for those that like to play with dead things. 🙂
If you purchased the download they are included in the folder 2nd file called Photoshop Content\English\Goodies\Optional Plug-ins\Plug-ins 32-bit\Filters. You will need to go all the way down that path to "extract" them. Regards, MM