You know, that's kinda funny. I really don't know "where" the novels will be released!!!!!
This new world of publishing is interesting. If a publisher in New Zealand releases a book that will be carried on Amazon.com or other online book sales services - where is it being released?
The marketing strategy I've proposed to them is to obtain several pre-release reviews. Then, when the book is released, send out Press Releases to those media outlets most likely to have strong interest in the novel. As the series is involved with the founding of the California missions, it would seem clear to me to contact media in those places where the missions now are. It also assumes the novel should be written in American English as it's aimed at Americans.
With the exception of O's and S's, the spellings appear quite acceptable to any audience.