It's not exactly like Assassin's Creed, but if you like assassin type books I do have a recomendation. I just finished reading an amazing book called The Last Umbra by M.R Chavez. He has a unique take on the Japanese culture by bringing a samurai warrior to early California. The book is full of action that kept me entertained from beginning to end.

A Historical Adventure, Action-thriller. It is focused on the admiration for the Japanese warrior class. This book tells of not a pride filled Samurai, but instead, a ninja assassin on a quest in gold-rush era California.

If anyone want to check it out you can find it here.

http://www.amazon.com/Last-Umbra-M-R-Chavez-ebook/dp/B00W01KUD4