d3

http://www.quora.com/How-do-I-learn-D3-js

d3 learning thread

Build JSFiddles:

http://jsfiddle.net/gregfedorov/Qh9X5/9/

Follow these tutorials

http://bost.ocks.org/mike/circles/

http://bost.ocks.org/mike/join/

https://github.com/mbostock/d3/wiki/Selections#data

http://bl.ocks.org/mbostock/3808218