I'm in Canada. I reformatted internal memory per your instructions (thanks for that) and did indeed get the applications + books back. To my surprise, however, when I first restarted after the formatting, everything was in German and most of the ebooks are German!
I changed the language settings to English, so that's not a big deal.
Prior to my reformatting internal memory I did upgrade the firmware to 15.1. I notice that I'm still at 15.1 after the reformat, which is good.
Is there any other way for me to obtain the original books shipped on North American units?