I wrote this bookshelf package for my own web site at pinds.com. For background information, please visit http://www.pinds.com/download.
The latest version lives in the OpenACS CVS repository.
Install the package on your system, mount a new instance somewhere on the site map, make sure you have admin permission on the instance, and then visit the URL where you mounted it. Now you can add your first book.
It's meant to support both single-user publish-to-the-world style bookshelf, and a collaboratively maintained bookshelf for members of a community.
If you want to inlcude your bookshelf on, say, your blog page, you can get it in two versions:
The package fully supports multiple instances, i.e., you can mount several instances in your site map, and they'll stay properly isolated from each other.
Only supports PostgreSQL (please do port to Oracle if you want to).