Another gem from MacOSXHints
covers a method, albeit not exactly pretty, for labeling TV video files you
bring into iTunes as TV shows. This helps with organizing videos and I believe using the new Search Bar in iTunes 6
(Edit > Show Search Bar).
The MacOSXHints post offers a command line tool by the name of AtomicParsley for doing the editing and applying the correct label, while a commenter on the post created a GUI wrapper for it. Make sure you follow the instructions when using a tool like this, because it's playing around with some real low-level stuff in your video files.
While these are some handy tools, I'm much more of a fan of simply editing all the files in iTunes using Get Info and applying a Grouping label. A Smart Playlist can then organize everything for me - no fuss, no muss.