Although there are a few hints that relate to this, I think I've streamlined the process for taking a podcast episode (such as from the excellent KEXP Song of the Day podcast) and automatically stripping the podcast ID3 tag, deleting the podcast episode, and re-adding the track to your iTunes Music Library as a regular MP3 file.
First, you must download fixid3tag. Then in Terminal, type gcc fixid3tag.c -o fixid3tag (you must have the Developer Tools installed). Put the fixid3tag binary someplace; I put mine in ~/Documents.
Next, take the belwo AppleScript and put it in ~/Library » iTunes » Scripts. The first couple of lines are used to specify two important file locations -- the location of the fixid3tag binary, and the location of your temporary folder (I used ~/Desktop/Fixed.)
Mac OS X Hints
http://hints.macworld.com/article.php?story=20080518143935527