You can now pre-order the ebook version of The Platinum Triangle on Amazon. If you purchase it today at the pre-order sale price, the e-book will be automatically downloaded to your Kindle on the release date, which is June 8, 2015. Pre-order information about the paperback version of the book will be forthcoming.
Keep in mind, if you use a different e-reader like Barnes & Noble Nook or Kobo Glo, etc., you will be able to purchase both the electronic and paperback versions of the book on the release date.