When I came up with a plan to publish my first book, I knew it was going to be a challenge to market a collection of poetry. But I was heartened by the fact that my author was a teacher and had a group of students who wanted to buy her book and would likely agree to do online reviews. I naively thought that this would be an easy way to get some presence on Amazon and perhaps get additional copies sold.
What I didn't realize was that Amazon has certain rules about posting reviews. First of all, friends and family are not welcome to review an author's book. Thus if the review says something that implies a relationship outside of reader/author, the review will never appear on the web. Secondly, if your potential reviewer has never purchased anything on Amazon before and just gets a user name in order to leave a review, Amazon will not allow it. You must be an Amazon customer to leave a review, and that means that you buy things.
Then I thought that Amazon wanted to grant reviews only to people who bought the actual book from the site. However, that hasn't been the case. A review showed up from an acquaintance who reviewed the book but had not purchased it on Amazon. Another things to keep in mind: you are supposed to disclose in your review if you got the book for free as part of a give-away promotion.
Goodreads.com or LibraryThing.com are good alternatives for Amazon in terms of ease of reviewing. Anyone can join and review any book they want. However, it may be that most people won't want to create yet another internet account just to review your book.
However, for someone that likes to read, Goodreads or LibraryThing could be a new favorite site. A way to remember books that one wants to read eventually, keep track of books read and rate them, share recent reads with friends.
Well, it's late. But I just realized that when I was looking for the answers to how to get reviews to show up I could not find the detailed answers I wanted. So hopefully this will help someone else doing the same.