I've given away 40,000 copies of my book. I hope Dharmesh posts here because they just launched a book that's going really well.
Here are some of the things I've learned in marketing my recent book (http://InboundMarketingBook.com )
That's all I've got for now. I've got a longer blog article I'm working on that talks about marketing books. Stay tuned.
On top of the suggestions by prior posters (which are all great), I'll offer up a case study for people to chew on...
One of the best social media marketing plans (for a book) that I've seen in a while was done for Dan Pink's last book, The Adventures of Johnny Bunko. The book is a pretty concise career guide in manga form. Here's a list of what I observed. I put links where I could find them so that you could get a sense for how things came off...
Hope someone finds this helpful. I thought it was pretty amazing to watch over the course of a year. Just a job very well done.
Full Disclosure : I do not know Dan Pink, but I do know the social media consultant (Jeremy Epstein) that put together the social media campaign for the book. The entire post above, however, was compiled by me (thus all errors are mine). The good part is, if you find any of this compelling, you can just go to his web site/blog and read... He blogs like a madman and there's tons to absorb... hmmm, maybe I should convince Jeremy to join this site... (think, think, think).
This may seem obvious, but I'm going to post it anyway.
If you're still writing a book, start telling people about it right away and, if they're interested, get their contact information and tell them you'll let them know when the book is published.
I just spent the last four years (part time) writing my book Conferences That Work: Creating Events That People Love. During this time I built up a long list of folks with whom I fell into conversation in the darnedest places - on planes, while waiting for my car to be fixed, while staffing completely unrelated trainings, while running conferences, etc.
The book was published last month and I've been working down the list, sending a personalized email to each person. The personalization just reminds the recipient how we met and then I add one of several short pitches for the book.
To my surprise, almost everyone has responded enthusiastically and told me they're going to buy the book.
In a while I plan to email these people again and ask them for feedback and recommendations (and permission to quote if favorable), and encourage them to review the book on Amazon or their blog if they have one.
I'm also not going to spend any time on bricks and mortar bookstores, but I'm considering marketing to libraries, since my book might be considered a good reference tool by librarians, even though it has a more radical agenda...
Three small points to add to the really outstanding answers above (I truly wish I had this advice when earlier this year.)
Everyones answers were great. Lots of useful tidbits. I figured I would share my plan to date and update it as I progress. The book became available last week, so I don't have much data yet.
Accomplished to Date