Claire Avery's "Hidden Wives" looks very appealing to me, also. Like Sara said, I usually avoid this kind of books, because these people are so often credited with belonging to my church which is not the case. The bookc cover caught my eye right away, and then Clare's comments sealed it for me. Gotta get that book :)
If I know there are going to be "sequels" to a book, I wait till the whole set is out to read even the first one. If you have to wait six months or so in between, you've forgotten half the story (or, at least, someone as old as I has).