I used to help edit a small-press science fiction magazine. This put me on the mailing list for publishers for preprints and reviewer's copies of books.
The magazine has long since folded (thank goodness), but despite my letters to the contrary, the books kept rolling in for another year or so. I have reviewed some of the more interesting-looking ones, as well as a few other books I have read. I had fun writing these reviews; I hope you have fun reading them.
Some of the documents linked to below are reviews of more than one book. I've listed each book separately.
Minor note: You'd think having free science fiction sent to your doorstep would be neat (and it is, sometimes) but you'd be amazed at both the speed at which it piles up and how low the quality tends to be. Sure, once a year you get the new Kim Stanley Robinson, but boy, after the third first book in a trilogy by a previously-seen-writing-Aliens-vs.-Predator-novels author shows up, you begin to long for the days of just visiting your public library and checking out what you want.