I wrote a couple of blog posts that list some areas to get started with Dojo.
Be a Dojo developer and more
Getting your Dojo on - odoenet
I think the main places to look are going to be the update Dojo docs.
Dojo Tutorials - Dojo Toolkit
They have really organized stuff much nicer than before.
I think the modules section is important, especially the CDN lesson.
But there is a plethora of good info in all the docs for you get familiar with it.
There is also the sitepen blog.
Hope that helps.
Another option would be to use Esri-Leaflet, which does not use Dojo.
Esri Leaflet group on Geonet
That being said I do like leaflet for simpler applications.
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