How do you get the free copy? E-mail me and tell me you want to do the review, then I'll send you a coupon code for the Smashwords site which will allow you to download the e-book for free in whatever format you want.
I would hope you would also go to other sites such as Smashwords, Amazon, Barnes & Noble, and Goodreads and leave reviews there, but I won't hold you to that.
Also, I will not hold you to a positive review. I would hope for one, of course, but I'm not going to scream about a negative review if that should be what you give one of my creations.