If I could recommend a way to learn d3.js:
1. Read Scott's book (and code the examples).
2. Think of some simple charts you want to make (and code them).
3. Use #d3.js@freenode, Stack Overflow, and see if some of the articles at http://www.d3noob.org/ fit what you're trying to do.
4. Go to http://bl.ocks.org/mbostock, be inspired, fork the code, and apply it to your own idea.
Repeat #3.
Ideally, find some kind of community where you can discuss with and help each other out regularly, but I don't really know of such a place, and it can be hard to find someone to do this with physically outside Paris, Berlin, NYC, and SF.