One suggestion I would have is to tell the users upfront about the affiliate links. I don't have a problem with them but the amazon links are minified.
For example this is the link the user is shown: http://amzn.to/bkB3gr This is what it expands to: http://www.amazon.com/gp/product/0688014291?ie=UTF8&tag=...
By not mentioning the affiliate link and only showing an obfuscated link it gives the appearance that you are trying to pull something over on the user.
I think a statement on the front page saying that links are affiliate links, or just putting the actual links on the pages would help with gaining the user's trust.
Great site:)
edit I know see this on the site: external links to amazon are through their affiliate program
Great:) Back to reviewing books to buy!
Aside from that, here was my experience with the book back in the 1980s: I was managing a small family entertainment center and I was working too hard and was on the verge of being fired. I was told to buy the book. When I got done with it, I applied what it said, I dramatically reworked procedures to be clearer and simpler and found myself with too much time on my hands and the center was much easier to run. I wound up going from being on the verge of getting fired to getting multiple promotions and transfers to better locations.
Some people don't like the book, claiming it's too simplistic, but it's short, and both easy to remember and apply.