iTunes won't start

[Jim Shimozawa]

Hello iBook people:

I never had any problem using iTunes until yesterday.
Now, starting this app gives me the following message:
         "The iTunes Music Library file cannot be read because it does 
not appear to  be a valid library file".

I popped in an audio CD, double clicked a track to see what happens - 
same message.
Downloading and reinstalling this app generated the same message.
The only suspect I can think of is iClean v6 by Aladdin Systems which I 
ran recently without thinking too much.

Do I need a Norton, Disk Warrior, or TechTool to fix this problem?
Repairing permissions did not help.
Thanks in advance.

Jim

12" iBook 700/640/CD/20 running OS 10.3 (Panther)
(iTunes is the latest version)