The thing with commercial publication is, you don't "use" a publisher like a for-pay service. They buy rights to publish your work, and they usually pay an advance against any royalties the book might earn you. As such, because they're fronting all the costs of publication (and that's far beyond just the physical printing of the book), they're selective in their purchases.

If you're looking into a self-publishing service, I'll leave the answer to someone with more experience. I'd probably just go with Lulu or CreateSpace if I wanted something printed.