I have scheduled Shades of Empire to be free in the Kindle store tomorrow. Assuming Amazon's programming doesn't go belly up on me (again), it should be free at about midnight tonight, US Pacific Daylight Time and stay free for approximately 24 hours. This is most likely the last time this book will be free on Kindle.
I will confirm tomorrow and post links for all the Kindle stores: US, UK, Germany, Spain, Italy, and France (not that anyone in France will care!).