Kindle for PC: Finding your notes file

I'm blogging this mainly because I spent hours trying to export my highlights/notes from an ARC (Advanced Reader's Copy) of Juma's Rain. The only thing you can find online is how to export notes from a Kindle reader (and usually a store-bought book) to a PC but not from a PC to... well, PC.

So basically I had two problems:
1. I was reading an ARC, therefore it was not an Amazon book (at least not yet - it releases next week), and therefore did not appear in my online highlights f...