Cataloging, organizing, sorting, and rating media in a personal collection such as, for music, the user's inventory of compact discs, vinyl records, or cassette tapes, or for print media, the user's personal inventory of books, with the intent of identifying what a user lacks to make a collection complete, for example, which releases in an artist's discography are yet to be acquired to make the user's collection complete, and facilitating the user's ability to locate these missing items via l...