Re: Aikido Books
"The Art of Peace" by Morihei Ueshiba
"Aikido and the Harmony of Nature" by Mitsugi Saotome
"The Way of Aikido: Life Lessons from an American Sensei" by George Leonard
"The Secrets of Aikido" by John Stevens
"The Spirit of Aikido" by Kisshomaru Ueshiba
There are more that enriched me, but these are my top five, in order.