Have you head of HarperCollins First Look? It's a program where readers receive books and supply reviews in return. Books from many genres are available.
HarperCollins requires registration to participate, and the reviewers are selected at random. If you're game to try, visit http://www.harpercollins.com/members/firstlook/index.aspx?HCHP=FL
If you are selected as a reviewer, you may choose your genre. HC will contact you when a book in your chosen genre is available. Books are offered monthly.
I have not tried this program, but it intrigues me. I found it while clicking around on the Net.