Kendall Grant Clark has published an interesting series of articles on the O'Reilly XML portal around the issue of creating a personal electronic catalogue of your home library. He's nicknamed the project LCC@Home as LCC is the cataloguing system of the Library of Congress in the USA.
My first significant computer project as a child was to try and catalogue my books at home (on a Sinclair ZX81 and later a Sinclair Spectrum). The database (in-memory BASIC data structures) and sorting worked (bubble sort), but the limited memory made the system pretty useless (I hadn't heard of merge-sort and how to manage large off-line storage with small memory at the time).
It is interesting to see that we're eventually reaching the time when it is possible to use on-line directories of data (such as the Library of Congress and the various music and movie/film databases) to produce high quality catalogues of home material.