Itunes folder & Itunes library do not match: Different Info

[Ctunes]

I've spent loads of time organizing the info in my itunes library (artist, genre, etc.) and almost all of the time this info is matched in my itunes folder. BUT I recently added an audiobook, separated by chapters, and while I have tweaked the info in my library so that it is correct, the info in my itunes folder (mainly the author's name [artist] and track numbers) refuses to change to match what my library now says. I tried to change the 'details' in the 'properties' of each file, but this renders it useless in itunes. What is going on??