Prototype and script.aculo.us: You Never Knew JavaScript Could Do This! (Pragmatic Programmers)
Christophe Porteneuve
Published by: Pragmatic Bookshelf on December 2007
A very detailed descrition of these 2 javascript add-ons. I found this very hard going although you can just download and install these two libraries and start using straight away through the section on script.aculo.us.