On Nook devices and getting to your purchased content
Nook First Edition, Nook Color - plug your Nook in to your computer. The .epub files are right there.
Nook eInk models with an SD card - there is a mod which does not require root which will sym link the folder from the internal hidden partition to the SD card. -
http://nookworks.blogspot.com/2012/0...d-card-as.html
Nook eInk models without an SD card slot (Glowlight, Glowlight Plus), Nook Tablet, Nook HD/HD+, and the Samsung Nooks to date- you must* root the device**.
*The guy who made the eink sd card mod says it -might- work on the Tablet, but as far as I know no testing has been done.
** I know the eink Nooks, and the Tablet have been rooted, I am not sure about the HD line nor the Samsung line. But as the tablet lines all have SD card slots they should not be overly difficult to root.