The following is a list of resources where you can learn more about using Neo4j with Ruby.
Neo4j.rb Screencast Series
How NEO4J Saved my Relationship by Coraline Ada Ehmke
Why You Should Use Neo4j in Your Next Ruby App
Query or QueryProxy?
Getting Started with Neo4j and Ruby
Example Sinatra applications
Using the neo4j gem
Using only the neo4j-core gem