I have been racing in open water swims for over 40 years in hundreds of different competitions. I think I have read most of the books published on open water swimming in the US, the UK and Australia.
Steve Munatones' book is probably the best resource available for anyone who is interested in open water swimming. He includes useful focused information on the tactical, strategic and technical challenges of open water swimming which is extremely useful for anyone from a fledgling triathlete to a medium distance open water swimmer who wants to step up to the challenge of marathon swims. Open water swimming is very different from pool swimming and racing outside the predictable confines of a swimming pool has challenges that constantly surprise new participants. I haven't seen any other publication with the wealth of specifically useful information that Steve shares here to help shorten the learning curve for new swimmers and which contribute useful insights to more experienced swimmers.