Through these many years of writing and publishing, I've come to notice a trend.
First, there were books on how to write...and then writer's conventions, seminars, and other events, all for the sake of teaching you how to improve your writing and breaking into the publishing business.
Then, getting a publisher required an agent, a person who took a percentage of your pay in order to act as a gatekeeper.
And once you were published, you'd often times have (or hire, if your publisher didn't) a publicist to take care of setting up events and such.
Now the game has changed, and authors are striking out on their own. But to do it "right" you'd have to hire professional editors, cover artists and those who could convert your manuscript for publication as an e-book or paperback.
And now that agents are slowly losing their grasp as gatekeepers to the publishing world, they and others are now willing to take on all the heavy lifting of getting a book ready for publication, as e-stributors.
Which goes to show something that I've always maintained (and was just telling a friend of mine the other day): There's a heck of a lot more money involved in the business of writing, than in the actual writing itself...