Data Crow is a powerful free Java-based media organiser.
The program includes modules to help you manage all kinds of media types: audio CDs, books, images, movies, software and a whole lot more. If that's not enough then you can create new modules of your own.
One major problem with this kind of tool is that it can often take you an age to get started, as you'll have to manually enter so much information. Data Crow does its best to minimise this, though, by importing information directly from the media files themselves (music metadata, say), and can grab further details from online services like Amazon.com, Imdb.com, Softpedia and MusicBrainz.
And a host of additional advanced features includes an optional internal web server, a loan management system, and in-depth reporting which can produce detailed catalogues of your collection in both HTML and PDF.
All this power does come at a price, though: the program is extremely complex, even when set to "Beginner" level. There are menus, tabs, toolbars and many other elements to explore, and the overall design is less than intuitive so at first you'll be a little confused. This doesn't last forever - there's lots of help, and once you've figured out the basics then the program works just fine - but just be aware that you'll need to put in some work initially to get over Data Crow's steep learning curve.