US customers can purchase a copy for $12.99 from the US Amazon Kindle Store. An EPUB version, compatible with Nook and Abode Digital Editions, is also available for purchase from the US Barnes & Noble Nook Store. Prices are set by the bookstores and their distribution agents, so may vary from place to place.
Having created the mobi file myself, I can tell you that eBook conversion is not for wimps - I have certainly learnt a lot along the way, which I will hopefully be putting to good use when I (finally!) come to publish the ebook version of my own book, Squaring the Circle, which is still a work in progress. Still, I hope you will appreciate the effort I went to in order to create a user-friendly but also attractive virtual reading experience, complete with links between place entries and the relevant entry in the notes section, a dedicated chapter for all chart drawings, complete with links in the alphabetical list of places, and fully referenced endnotes at the end of the Introduction and Notes chapters.
For those of you who don't own a Kindle, don't despair - you don't need to. All you have to do is download the Kindle Reader app onto your home computer, netbook, tablet or smartphone and then link it to your Amazon account. Then every time you buy a Kindle eBook, it will download into yoru Kindle library. Nice and easy!
If anyone would like to review TNATC, please contact me via my website.