Glad you found the cause of the books not showing up. To bad it's a corrupt db.
As far as I know, the only way (besides restoring it if you took a backup) to fix it is to logout and login again (which will cause it to be rebuilt, all your books will still be there, some stats will probably be lost).
Either logout/login, or wait until one of the Davids or another of the great people here pop up and tell you what's the best solution.
