manual

Working through these two links will give you a lot of information:
http://rubyonrails.com/docs
http://railshandbook.com/

best is to buy these two books:
http://www.pragmaticprogrammer.com/titles/rails/index.html
http://www.pragmaticprogrammer.com/titles/ruby/index.html

everything you need to know about rails and ruby.

HTH