This Repo contains two different applications
1) "library" is the rails application. Start that application up by the usual "rails server" command.
Browse to /books to see where the action is at.
2) "railsClient" is where the C# client resides. You can compile the .cs file in there on the command line on linux with "$ gmcs /railsClient/railsClient/Program.cs" or use visual studio.
To use the executable generated, just follow it's instructions, specifying the full url to the /books controller when prompted (your IP address will be something like 192.168.1.x, right?)