So I did just that. Find it at http://ethicalmall.blogspot.com/. It's not really a blog, as it won't be updated frequently. But when I buy things from any of the featured shops I will write about it, commenting on the usability of the online store, the speed of delivery, quality of the goods and packaging and customer service. I have also invited a few of my friends to submit reviews, otherwise there only would be one update every three months or so when I buy something (I'm no shopaholic). Blogs are easier to set up than websites, though, so that's the way I have created it.
I hope other people will find it useful, but even if it remains nothing more than a glorified version of my "favourites" folder it will still be worthwhile.