This tutorial on OTNshows you the installation of Ruby/Rails with Oracle and how to develop highly efficient and functional Ruby/Rails applications. You will gain the knowledge needed to create powerful Ruby/Rails appplications with Oracle backed for your enterprise.
Read more articles about Ruby/Rails and Oracle on OTN:

• Ruby on Rails with Oracle FAQ
• Tips for Optimizing Rails on Oracle
• Connecting to Oracle from Ruby on Rails
• Accessorize Oracle Database with Ruby
• Guide to Ruby on Rails Migrations
• Ruby on Rails on Oracle: A Simple Tutorial
• Tagging with Oracle and Ruby on Rails
• GRails on Oracle for Java Developers

There are also Oracle pages on Ruby on Rails Wiki.

• Oracle in Ruby on Rails
• How to Connect To Oracle(latest)