Every Friday I take the initiative to search through thew newly free titles on Amazon, and to identify those that might be of interest to trans* readers, fans, and lovers. Even if you don't have a Kindle, you can still download the titles through one of Amazon's free reading applications, and covert it (if need be) with Calibre. I can tell you I do most of my reading on my tablet, using Kindle for PC, and it works beautifully.
Please do be sure to check the price before downloading anything, though, as most freebies are limited time offers, and some are specific to certain regions.
Gender Bender Battle: Transgender Body Swap Erotica Stories
Our Transsexual Au Pair Bundle (4 TS Stories)
Surprise in Her Pants: Naughty Transgender/Futa Box Set
Servicing the Debt and other Femdom Stories
Pink Ninja Femdom
Peeping Tom's FemDom Payback
Jenna Takes Control (And Roger Learns Humiliation)
The Prison Secretary: A Story of Teasing/Denial & CFNM
How To Be A Cosplay Girl
The Mentors--Metamorphosis of thought and form
The Scottish Bitch