First, allow me to direct you to a very good article by Jon at Crimespree magazine.  I’m not much into Jon’s genre, but I’ve been a reviewer at Amazon for quite some time.

Before Amazon changed its ranking system, I was high enough on their rankings that I took some pains to keep my local media from finding out (lest they bother me).  The majority of my review solicitations were quite faulty.  To wit:

• Many wanted me to review galleys.  Uh, no.  If my only compensation is the actual book, you expect me to forego that?
• One spammed me weekly about her children’s fantasy until I finally reported her to her provider when “no” and “get lost” did not suffice.
• Lots paid no attention to the sorts of things I had reviewed in the past.  Does my body of work look like I read a lot of Christian-themed murder mysteries?
• Some wrote so badly they unsold themselves.  If this is how you write when you are trying to get my attention, what kind of book did you commit?
• A number wanted to send me e-copies.  While I can accept offering me the option, what that essentially says is that I wasn’t carefully selected–I was spammed, along with many others, as there is no cost to sending e-copies, thus no reason not to mailbomb the entire Amazon reviewer base.
• Few sent me anything with even a hint of personal touch.  I wasn’t looking for flattery (and in fact was turned off by it), but some sincere reason:  why me, and not someone else?

Most radiated one of the greatest turnoffs about authors (and you’d be surprised about some well-known names who resemble this remark):  dividing the world into two groupings, a) those prepared to buy/promote/fanboy their work, and b) useless individuals.  I don’t go to writers’ retreats and after several tries, I’m not interested in local writers’ groups.  There is just too much of this, and the pain is not worth the gain to me.

So how do you get reviews for your published work? Realize:  you’re asking someone to commit to a thorough read of a book that 80% of the time will be mediocre (that’s just the average).  See it through his or her eyes, spending several hours of life in what the odds say will be suffering.  Explain why s/he should believe that it will not be suffering–not everyone, just that person in particular.  Not with flattery but with examples of your book’s merits germane to what the reviewer seems prone to review.  Do it professionally yet personally, conveying the message that you will gladly accept even a criticism-filled review.  Act like a credible professional contacting another credible professional.