D3.js Getting started (again..)
The same questions as some years back: How to get started with it ?
The good news: There is plenty of material out there aboutD3, books, websites, tutorials. I purchased a couple of books from Packt Books and O’Reilly as PDF version, I think they have the most books, though most of them based on earlier D3 versions.
I wont recommend a specific one, most follow the same principles, a short intro to the DOM, explain the D3 basics followed by more or less complex samples. As with any other technology or programming language you learn most hands-on, there so many examples and good tutorials available. I never attempted to understand everything, understand the concepts, dissect existing visualizations and get creative !
What I would go for are general books about visualization concepts, patterns, types and terminology. Some I did read:
Beautiful Visualization, Julie Steele(2010)
Visualize This: The FlowingData Guide to Design, Visualization, and Statistics, Nathan Yau, (2011)
Data Points: Visualization That Means Something, Nathan Yau, (2013)
If you want to have it slightly more interactive and with less reading involved, go for the Udacity online classes by Google, once covers D3 and visualization and its free.
Udacity D3 course