I am actively working on Books 1 and 4. I'm looking to self-publish each book, while making them available in four different formats; ebook, paperback, hard cover, audiobook.

Originally, I thought about going through a POD service, but actually, when I thought about it, they don't really do much. It came down to price. The price of books from most companies were pretty high. So I looked for both price and services.

Here's what I've decided.
For ebook; smashword (it seems to have a lot of range)

For paperback: createspace (amazon is available world-wide and the retail price of books can be adjusted to make them more affordable)

For hardcover: of course, the retail price is a bit high, but that price can be 'discounted'. the problem there is that the author walks away with literally $0.16 cents per book in royalties. But should a reader really want hard cover so badly, at least it's available.

Some of these services are shunned or looked down upon but I don't think it's the services themselves that are the problem. Using these allows for better investment in editors to ensure a better product, which is what we're after at the end of the day.

Will it work? Time will tell.