If money's tight, BookBaby will take your ePub file (which you need to format yourself) and then distribute the book to the online sellers you choose. There's no fee for this, but BookBaby takes a 15% commission of all sales.
Smashwords, on the other hand, works strictly on commission; its rates depend on whether you sell your book at one of its partners or on the Smashwords site. Booknook's rates depend on how complex your manuscript is -- a medical textbook with multiple illustrations per page will cost more than will a memoir with minimal graphics or charts. For this reason, many formatters/aggregators charge more to translate nonfiction than fiction. Most will take a look at your manuscript and then quote you a price.
A large bottle of aspirin and an even larger calculator — or perhaps the other way 'round — will come in very handy as you're making some of these decisions.
How do you choose? It depends on your needs. For example, we're still deciding on an aggregator and our criteria include the ability to translate into multiple formats (from our word processing document), how long the company's been in business and how many clients it has, what the overall pricing structure would be for our nonfiction book and what the aggregator charges for redoing any pages.
After your book is formatted correctly, you need to figure out how and where to sell the book. You have a choice of working with aggregators that, as noted above, will also distribute your book for a fee, or you can skip the middleman and work directly with the e-sellers.
Currently, the Big Three e-book retailers are Amazon, Barnes & Noble and Apple's iTunes.
Amazon has a program called Kindle Direct Publishing Select (usually known as KDP Select). Basically, you agree to list your book at Amazon exclusively for a term of three months (which you can renew). The book is eligible for Amazon's Lending program, as well as its Countdown Deals (which offer limited-time discounts) and other promotions.
As in all contracts, the fine print is important. For example, with Amazon's KDP Select, you have a choice about whether to take the 35% royalty or the 70% royalty. Your first thought would be to take the larger percentage, right? Well, if you take the 70%, Amazon assesses "delivery charges" (yes, even for digital books) based on how many megabytes of storage the book requires. And they do that for multiple countries — Canada, India, the U.K., etc. It works out to pennies per MB, but still... Amazon doesn't charge delivery fees on the 35% royalty, however.
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