Not that I am, by any means, an expert on the subject, but I thought I’d offer some personal marketing experiences for the self-published:
Any promotion where your book(s) are part of a giveaway isn’t worth your time or effort. I’ve participated in about 10 blog hops, book tours, contests etc. in which people could enter to win a free copy of my book. As far as I can tell, I’ve never made a sale as a result of one of these. Sure, people are all gung-ho for a freebie, but if they don’t win, they don’t buy. It makes sense. If someone doesn't win, they probably forgot they entered. Even if they thought the book sounded fabulous, they likely don’t even remember it by the time the giveaway is over. If you are doing a giveaway because you just want to get your work out there, then these promotions are fine. If you think your sales might improve, don’t hold your breath.
Some paid advertisements are better than others. This one’s a no-brainer, but the trick is to figure out which sites are worth what you pay. In my experience, there aren’t many paid sites that get you more in sales than you shelled out for the ad itself. If it’s more than $25, think long and hard about it, unless you know books in your genre do well on that site. And the only way to find that out is to ask authors in your genre where they advertised with good results. And make sure the author you ask is someone who will give you the real scoop – it doesn’t help if they exaggerate their sales just to make it seem like they’ve sold more books than they actually did.
If your book is going to be free on Amazon, make sure you promote it! Just because your book is free on Amazon doesn’t mean people will know it’s free. I used the Author Marketing Club’s Free Kindle Book Submission Tool . It lets you sign up for a bunch of promotions, most of which are free or a nominal fee, on the days your book is free. Make sure you sign up as soon as you know when your free dates are; many sites require advanced warning so don’t wait until the night before. I ended up with over 4,000 downloads of Special Offers in the 2 days I offered it for free and was #2 in free sales in my genre for about 10 hours during that time span!
Don’t pay a crap-load of money for a contest. You know what I’m talking about, pay hundreds of dollars to enter your work in a contest for Independent/Self-Published authors so you can say you’ve won the coveted Obscure Literary Guild’s Gold Medal. I have no specific evidence, but I’m pretty sure these are scams. Use a fraction of the money and slap your own “medal” on your book’s cover or webpage if you feel you need validation to make more sales. There are only a couple of literary awards that, when associated with your work, are going to make people stand up and take notice and I’d bet the Pulitzer people don’t ask for a fee. Even if they do, if your book wins one of those bad boys, your sales are going to go up so it’s worth the cost.