I found a neat site to catalog all your books, movies, cd's, video games and software.
It is so simple. All you have to do is either scan in the bar code of the book with your webcam or, do like I do, type in the ISBN or Bar Code (usually found on the back cover of the book).
It took about thirty minutes to enter 76 books (and one of them I had to manually enter the information--it is a very old Scholastic book). If you would like to visit my library, it is Crazy4Books. Go take a look. As I have time, I will scan the covers of the books that do not have images and add them.
If you are interested in organizing your stuff, GuruLib could be the site for you.
This is a screen shot of the Juvenile Biographies that I have downloaded to My Library.