I find the best way to start learning something new is to identify a fun but simple project that has options for expansion, and start working on it. You want the project to be one that is simple enough to not get discouraged quickly, but that is flexible enough to continue with as you get more proficient.
The reason I say find a project like this, is because if you don't have actual problems to solve, you won't know what to read about. You can read about rails routing all you want, but until you have a reason to use rails routing in any sort of complex way (resourceful nested routes, like a user has many photos => /users/1/photos) you can't really do anything with it.
Once you have a project and have questions, this is a great way to get help, however, without a project we are all flying in the dark with you :)
setup for Mac OS X (not very different for Ubuntu just apt-get rvm)
http://pragmaticstudio.com/blog/2010/9/23/install-rails-ruby...
Get started->
http://railstutorial.org/
http://edgeguides.rubyonrails.org/getting_started.html
http://rubyonrails.org/screencasts
http://ruby.runpaint.org/
http://weblog.rubyonrails.org/2010/8/29/rails-3-0-it-s-done
http://railsnotes.com/rails-3/
Why Rails, interesting anecdote from how 2 pythonistas decided to go rails.
http://blog.brandonbloom.name/2010/09/how-two-pythonistas-ac...