Actually, self-publishing is not just in digital eBooks. There are a whole slew of means for getting into print. Vanity presses have been publishing authors for decades, at a price.
LightningSource and CreateSpace are two Print-On_Demand options that have a low cost of entry. They only print books when they are ordered. You no longer have to order 2000 books at once and store them in a spare bedroom forever.
What I like about CreateSpace, which has now merged into the KDP (Kindle Direct Publishing) arm of Amazon is that you do not have to deal with fulfillment when books are purchased. They print books when people buy, and ship them, too.
The Biggest Problem, though, is Marketing is still up to you.