Book recommendation?

Hi,
I am interested in yahoo's yui and jack slocum's work.
Anything Ajax or Ruby on Rails.
I have "wung it" and implemented things but feel like I should crack open a book and learn it from the beginning. Who knows what poor assumptions I've made along the way by winging it.
Thanks

There are a couple free books on the web
http://www.sitepoint.com/blogs/2007/10/02/sitepoints-ruby-on-rails-book-is-now-free/

Free is great, thanks

BTW I love O'Rielly but I see his "definitive" Javascript book is 900 pages. That seems like too many for me. 2 kids under 3, quiet time is limitted

Free expired Dec 07, thanks though

I am sure you can just get a torrent of it then. It was free at one point so it will always be free.

Any other recommendations please?
IIRC There is one or two guys from here that wrote books, I just can't recall what their usernames were