I use this software for my DVD, Ebooks, books and music
http://www.delicious-monster.com/
you do need a mac however?
It allows me to type the ISBN in for ebooks(or scan the barcode with webcam for physical items) and then they are added to a section(shelf) of my choice, one of the thinks that makes it work well for ebooks is that a note - other field exists and is searchable. that is where I add the location of the file or files. oh and it looks awesome!