Control by Charlotte Stien is just $0.99
Seriously, at this price, I can't imagine how you can afford not to buy this book. I gave it an A-.
This is a classic novel, so there will always be free copies of it around. Reputedly it's femdom. I've not gotten around to reading it yet, so if you get to it before me drop in a comment saying what you thought of it.
Natural Law by Joey Hill is $5.49
I don't think this is actually a sale, but it's a reasonable price for this book and it is essential femdom reading. I gave it an A.
For any Brits in the audience:
Power Play by Charlotte Stien is £0.49
I gave this a B+ and it's probably the femdom book of 2012 as far as I'm concerned.
Red Grow the Roses by Janine Ashbless is £free!
I haven't read this, though I heard it's quite pain intense. Again, it's labelled as femdom by Mischief books.
Beyond Temptation by Lisette Ashton is £0.49
Another Mischief title labelled as femdom. I'll be reviewing this, so I'll let you know about it.