You're in the right place, and there is a thread on
Reading on the Touchpad somewhere nearby. I know it's a bit long, and we got off on a tangent a couple of times, but there's links to some helpful guides in there, particularly on how to install Preware, so you can install more than just the ridiculously small number of apps that HP provide.
I have dabbled a little bit with the Kindle app, and it seems okay so far, except it won't let me side-load books.