I have been running continuous FB ads for a while. For the most part, my sales have been slow but steady, and I attributed any upswings to when reviews were posted. I've been extraordinarily swamped at my day job for the last two weeks, and I let the FB ad expire. Of course, I was too busy to realize this. I was aware, however, that even though 2 very favorable reviews were posted in this time frame, there were no sales in the last two weeks. None. Zippo. Zilch. Yesterday, I finally noticed that the ad wasn't running, so I created a new one. In less than 24 hours, I sold five books.
I will cautiously conclude that the FB ads can be very helpful when it comes to upping sales. It's not helpful for making money, as I've paid out more for the ads than what's come in for sales. That said, I'm not all that concerned about the money at this point. I'm more interested in getting more people to read the book.
Here's what I've learned about FB ads:
1. Cast a large net. You want your "reach" to be big, but not too big. My first ad targeted women who like paranormal romance in the US,UK and Canada. It wasn't that successful. I've expanded the targeted audience to include both men and women who like paranormal romance OR the Black Dagger Brotherhood books, and added Australia, NZ, India, France, Spain and Germany. (Yesterday, I sold my very first book in España!)
2. Make the ad pop. The visual that people see is a small thing on the side of their FB page. A little image and a few words of text. The one that's worked best for me so far is a spooky looking guy, coupled with the header "Like Paranormal Romance?" and short bit about the book that I think would intrigue people. At least enough to click on the ad and get more information. Apparently, creepy faces get more clicks than other visuals (including the cover art, which isn't particularly creepy). Next time, I might try the ubiquitous shirtless hunk and see how that goes.
3. Change it up if it's not working. If you create an ad and it doesn't seem to be doing what you hoped, you can alter it or halt it and create a whole new one. A lot of this, unfortunately, is trial and error (and error, and error).
Is it worth the cost? Hard to say, but I suspect it is. A cheap paid ad on a well-viewed appropriate web site can cost a fair chunk of change, and they are usually only for a couple of days. The ad is targeted to people likely to buy the book, but your reach can be way bigger using FB. The bottom line is, I don't think an indie author can rely solely on free marketing strategies. Blogs and word-of-mouth are great, but to reach the most folks, I think you have to be willing to shell out some cash. You don't have to spend thousands, but if you want the best bang-for-your-buck, you have to be willing to spend at least some bucks or you're unlikely to get banged.