Overboard by Hank Searls
Attorney Mitch Gordon and his wife Lindy sail the Lindy Lee, their 40 foot ketch, from the San Francisco Bay and under the Golden Gate Bridge to Tahiti and Bora Bora. From the opening page Overboard sucks you in: Linda falls overboard during her time at the helm and Mitch wakes to find himself alone in the middle of the ocean. The story is told in flashbacks as Mitch retraces the course of the Lindy Lee to find his wife.
Overboard was clearly written by a sailor who has been to the places of which he writes. It was published in 1977, so it's a bit dated but no less accurate.
Beautifully written, lots of sailing, fantastic character development, and very believable, Overboard is a page-turner and a great read.