to mention Los Angeles gay spa, you would think they mean the gay bath houses, sex clubs, etc. such as the infamous 8709 club, long closed, where I learned about life and saw many celebs. but this book is not about the gay sex club scene, past or current.
LA has naturally occurring hot springs, and the LA City Spa and Health Center on Pico sits on one. It's co-ed and very legitimate. there is a lot more cruising going on at any gym. Now that might be a book worth reading: Celebrity locker room cruising at Gold's Venice.