Good morning all,
As a debut author and having recently published my first novel, I have found the most useful element is making contact with a reader or two and discussing your book with them.
This is I feel essentially important to improve your work. And certainly better than going for a direct professional review. I am not knocking a professional review, they are most important. But once a review has been done, if they have picked up on small errors it can damage your marketing.
A reader is impartial and I feel enjoys being able to give constructive feedback and helping an author.
So make a few friends on facebook who are readers not authors.
Do not use other authors, they are your competitors no matter how friendly they appear to be. A reader has no other axe to grind than wanting to enjoy your book.
Avoid things like Goodreads or Authonomy, 90% of the people on those sites are other authors wanting to promote themselves and their books. The feedback you are likely to get is going to disappoint. Stick with facebook, twitter and a blog.
I write this particular entry with one arm as usual, my surgery on my left arm has been done, I hope to be able to return to full blown writing in a month or two. I hope, depending on the titanium and the pain going away.
Here is a post I put on facebook
Why do Vampires fear the light? The answers in Origin, the mould breaking Novel as unique as Dracula. http://www.amazon.co.uk/ORIGIN-ebook/dp/B00CTS3ZX0/ref=sr_1_1?s=digital-text&ie=UTF8&qid=1369772912&sr=1-1
Have a great weekend all.