There's a fine, a very teeny, tiny one-atom thick, line between making your presence known and becoming a spam slut. I definitely want to avoid being known as a spam slut, but I also want to let people know I've got a book for sale.
What's worked for Seasons of Magick: Spring? Quite simply word-of-mouth. I announced on my blog each time the novella went live on a particular retailer. I tweeted each time the novella went live on a particular retailer. I guest-blogged over at Joan Reeves' Slingwords. So that's a total of seven things I personally did. That's all I did over the last three weeks since the initial release.
Then people started spreading the word on Twitter. Some are crit partners like @Faye Hughes. Others are total strangers like @Indie Elf. Other folks added Wild, Wicked & Wacky to their list of must-read blogs. Entertainment bots looking for keywords picked my book up and featured it. Business bots pointed to several of my business-related blog posts.
As I've said before, there's no sure-fire marketing method that works for everyone. You may need to experiment.
Nor am I relying solely on word-of-mouth for Blood Magick. It's the first book in Bloodlines, my urban fantasy series, so I'll do what I can to make sure it gets off to a good start. I'm already scheduling my blog tour, I've got my list of reviewers ready to go, and I'm planning some cool summer contests for this blog.