(1) Lightning Source is the major print-on-demand printer, and is used by independent self-publishers, self-publishing companies and traditional publishers. When you set up a new book in the LS system, you supply various information about the book (such as page count, publication date and cover price), and also have the opportunity to provide a long book description (formally called the "annotation").
The description is provided to booksellers, such as Amazon.com, and will be on their websites. If you simply type in normal text, it will lose paragraph breaks, and appear as one long and unwieldy paragraph online. Although Lightning doesn't say, so, you can format your text with at least some HTML commands, for paragraphs, boldface, etc.
(2) Here's a little "cheat" to get a book listed on Amazon before you are ready to sell it, perhaps to generate some pre-orders and to get visibility in search engines.
As soon as you have produced a version of the book that, while not quite ready for prime time, would not embarrass you if someone read it, approve it for printing through Lightning Source.
It should appear on Amazon.com within a few days. When that happens, upload a revised file to Lightning Source. Lightning will notify booksellers that a revised version is coming, and the bookseller sites will soon indicate that the book is temporarily unavailable The sites should allow people to place advance orders to be filled when books become available.
While it's possible that one or two substandard books may get sold with this strategy, it's not likely if you act quickly to suspend availability and have not done any publicity. Of course, you should complete your corrections ASAP and approve the final proof so you can start selling some books.