How To Publish A Book In 2 Weeks (For Less Than $250), article.
This is written from from a business viewpoint, not a high-literary one. But it's good to sometimes get an impression of how simple, cheap, and fast something can be done if one wants. And for somebody with the right mind and experience, fast does not mean sloppy. (Dickens was an amazingly fast writer.)
By the way, it sounds to me like the article says that print-on-demand books cost at least $10 per copy, but I asked the author and he says he gets them for $2.50.
The article does not talk much about fulfilment, meaning taking payment and shipping books. This is far from trivial, so an alternative is to focus solely on ebooks, which is successful for many authors already.