I published my Kindle Fan Guide several months ago, to quite some success. I’ve sold almost 300 copies so far.
I learned a lot during the process of publishing it. I had to log in to Amazon’s Digital Text Platform, though fortuately anyone can log in using an existing Amazon account. I then selected the option to upload a new book.
Kindle books have to be uploaded in HTML format. This turned out to be tricky, as I wrote the Guide in OpenDocument format in a word processor (NeoOffice). My word processor could certainly save as HTML, but the Digital Text Platform only accepts a certain subset of HTML.
So, I had to save the Guide as HTML, then go in and fix the HTML by hand using a text editor. Then I uploaded it. Fortunately, the Digital Text Platform lets you preview your work; fortunate, because the book didn’t look right at all. So I had to go back and tweak the HTML about a dozen times before it looked right.
Then I finished the process. However, Amazon’s systems take up to 24 hours to synchronize, so I had to wait until that was done. But when it was, I had a Kindle book ready to go.
As it stands, it might be easier to save the book as plain text, then add a few HTML elements for chapter breaks and such. But at least publishing on the Kindle is a relatively straightforward process. If you want to self-publish, the Kindle’s a fully reasonable choice.