Delicious Library - Delicious Library 3: Catalog your books, movies, music, software, toys, tools, electronics, & video games. Archive your life.
Helium Music Manager - You can take control of your music collection.
Tellico - Tellico is a KDE application for organizing your collections.
BookCAT - BookCAT is a powerful book collector database program which will help you catalog a book collection...
Readerware Book Database - The easiest, fastest way to catalog your books, nothing else comes close.
Waf Music Manager - Waf Music Manager is a lightweight and fast application that helps to organize the local music collection, such as large music files, edit, video formats support, high resolution, and many more.