Anybody has good resources (preferably free) on creating online visualizations. Not links to the d3.js documentation but good tutorials creating visualizations you often use on the internet. Like creating your own cool dashboard and stuff like that.
And later - look at examples (https://github.com/mbostock/d3/wiki/Gallery or http://christopheviau.com/d3list/gallery.html). IMHO it is the best way to learn D3.js and data vis in general.
Some other links: https://delicious.com/stared/d3js
not web-centric but the best source I know of offhand
(edit to add ..)
http://chimera.labs.oreilly.com/books/1230000000345/index.ht... is a viz book that uses d3. I haven't read it but the guy who wrote it does good work