Jorge,
I guess bookshelf hasn't been accepted as a part of the OACS package yet. IIRC there's a tendence not to take many new packages in the "distribution", but to give an option to download them separately from openacs.org. I think Peter is collecting a list of all packages and this list with download links should become available at the site if it isn't already there. I agree that at the moment it's a bit hard to find available packages for people not familiar with CVS.
