I have a fairly large collection of books, and I started to organize them years ago with Delicious Library. The biggest problem I had was that the majority of my collection is old and did not have cover artwork on Amazon. So I scanned and measured and input all of my 700+ books.
When I had finished, I was pleased with the results. However I wanted to share my collection with friends and family, and establish a lending library. The web export feature of Delicious was seriously lacking in my opinion, but I stumbled upon a program called DelciousSQLExport by Mark Burgess. It allowed me to export my entire collection as a SQL database and then write a front end to display it all. This makes browsing the entire collection on the web much better and it was good practice for me.