Free sells books. It sounds counterintuitive, but it's not. Think about it. Going free is like giving away a sample of ice cream. If the customer likes what they taste, they'll certainly come back for more. There's two ways of going free though--Permafree and KDP select. And although KDP selects oomph factor has waned, it can still help in getting your book discovered.
So what is KDP select? Simple. In exchange for 90 days of exclusivity with Amazon, you are allowed five days per cycle to run your book free. If you get enough downloads of your freebie, you'll see a sales spike from your subsequent higher placement on the sites popularity lists. When the program first started over a year ago, the algorithms measured one free download as equal to one paid sale. So days after going free, your book could shoot up the popularity list and get anywhere between a hundred to even a few thousand extra sales.
Two changes in algorithms later, ten free downloads is approximately now equal to one paid sale. But the theory is still the same. The more books you give away, the more sales you'll get after going back to paid. There used to be hundreds of free book blogs that would promote your free run. But after Amazon recently changed their affiliate terms to limit the number and percentage of free books given away, a large grouping of those free sites has dropped off. The juggernaut book blogs haven't changed though. With every free run, be sure to submit your book to www.ereadernewstoday.com and www.pixelofink.com. If you get listed on either of these sites, you're sure to have a good free run. Other good sites worth mentioning are www.addictedtoebooks.com, www.onehundredfreebooks.com, www.kboards.com, www.authormarketingclub.com, and www.ebooklister.com.
A new wrinkle has emerged in planning KDP free runs though. Bookbub, found at www.bookbub.com has over one million subscribers on its mailing list. And although it is a paid service, a number of authors have reported great results both with Free, 99 cents, and $2.99 sponsorships. The site is planned out by categories, with the prices ranging from $60 to $200 to list a free book. I know that's steep, but some authors have reported as much as a 10,000 book increase in their free runs. But again, results may vary, and discretion is advised.
KDP select is especially good for first time authors and authors just trying to build a name for themselves. Not only will you get your book into the hands of a number of new readers, but you'll be able to start building up your mailing list to use for future releases.
Permafree, or permanently free is the most effective way of getting your work to sell on the other venues like Barnes & Noble, Itunes, and Kobo. Naturally this works best when you have two or three books in a series and you set the first book free.
So how do you go permafree? Essentially what you do is publish your book for free on www.smashwords.com. If you follow the rather finicky guidelines for their premium catalog, your book will get distributed free to Itunes, Kobo, Barnes & Noble, etc...Then once the book is free on those sites, you wait for Amazon to price match to free.
Note: You can help the process along. Once your book is free on other venues, go to your books Amazon page. Below the sales rank is a link labeled "Tell us about a lower price." Click on that, copy and paste the url from Barnes & Noble, Itunes, or Kobo listing the free book, then send the feedback off to Amazon. Also, be sure to make sure your book description and book title match exactly on all sites. Amazon's bots check for identical wording when searching for free book on other sites--even the slightest change will throw off your changes of getting price matched.
While you're waiting to get price matched on Amazon, you should see sales of book two and three of your series. And although Itunes and Barnes & Noble don't have quite the audience that Amazon does, Romance, Erotica, Crime, and Science Fiction seem to perform well on all the sites. On the other hand, Humor seems to perform horribly on all sites. Side note: when going permafree, it is best to have the free book and the subsequent books to be in the same series. Having unrelated novellas or shorts seems to have little effect on audience building.
Eventually your book will go permafree on Amazon, and depending on how much people like your book, you should have yourself a nice self sustaining built in marketing campaign. The beauty of permafree and ebooks in general, is that all it takes sometimes is a short story or novella to do the trick. While there is and always will be a robust market for longer works, sales success is no longer contingent on 300-600 page books. You can make a good living writing 40-60 page novellas as long as they are part of a series.
Ideally you'll have enough titles that you can dabble with both permafree and KDP select. Also, you have the option of starting your career by using KDP select, then putting a book permafree after your 90 day exclusivity is up. Either way, free works.