I've written some suggestions for dealing with normalized data in a Redux app, and also collected links to other resources:

• I wrote the Structuring Reducers section for the Redux docs, which includes links to some articles on normalization, and how-to guidance on Normalizing State Shape and Updating Normalized Data
• I also just wrote a pair of articles on using Redux-ORM to help manage normalized data in your Redux store: Practical Redux, Part 1: Redux-ORM Basics and Practical Redux, Part 2: Redux-ORM Concepts and Techniques
• I also have links to some other articles on normalization as part of my React/Redux links list: Redux Techniques#Normalization

I format my API responses to be normalized already so it's very easy to consume on the client. I don't use any 3rd party libraries. However, I have the luxury of being able to design and update the server-side API as I go. You may be working with legacy code or code you don't control. If that's the case, check out Normalizr.

Havn't any best pratice about this, just load and morph it if necessary, it's just about encountered case. Some api's result don't fetch with our expected needs.