I read the rails routing short cut[1] by David Black. I liked the short cut. It did not go in to the detail that I needed to solve some issue but, it did explain how to use the console to figure out some routes. I started using rails before the resource routing and I found some nested routing to be a problem. David address the idea of REST and how it works with Rails by default. Overall a good intro to routing but you wont learn from using routes in everyday coding.
[1] Rails Routing