This script will apply user-entered text to the "Category" tag of each of the selected tracks. iTunes 5 or better.
(Note: In order to launch this PowerPC-era script on an Intel machine, it must first be opened and then saved using AppleScript Editor, which is located in your /Applications/Utilities/ folder. More information is here.)
Remember current track when quitting iTunes, pick up playing on next start
Select iPod tracks in iTunes and add them to iTunes
Remove iTunes tracks disassociated from files
Export artwork of selected tracks to parent or specified folder
Copy chosen tag info from one set of tracks to a different set of tracks
Renumber order of selected tracks