Femdom releases I've seen
Under her Thumb is an anthology edited by D.L. King. This was a March release and features many familiar names, including the the blogosphere's own Her Majesty's Plaything.
In terms of publishers, my attention was drawn (by a commenter I think) to Circlet Press. Their tag line is: The Intersection of Erotica and Science Fiction, Fantasy, & Futurism. There is a lot of BDSM and a good amount of that seems to be F/m or F/m/m/M or M/F/f/m/trans or - well, you get the idea. I suspect that you can expect quite a lot of sexy, extreme craziness, so if that's what rolls you then you should head over. There isn't any sort of helpful sorting system on their website, so unfortunately you have to read through all the blurbs.
Just published in April is Still by Ann Mayburn. This is book one of three and I'm pretty excited about the idea of femdom series. So much to look forward to! Also - check out the cover with the man tied up with blue rope. <le sigh> I like the trend towards tied up men or women's high heels on the covers of femdom books. I know that neither is exactly breaking any paradigms, but imho they're more suggestive of a being aimed at female audience compared to women in pvc/leather corsets with whips, which always seem to me to be aimed at submissive men.
It's not a book, but head over to submissive guy comics on tumblr and check out Femdom cartoons. They're cute, touching, hilarious and true reflections on BDSM and F/m. I am totally obsessed by them already. Why are you still here? Go!