Is your website easy to buy from? Tips to improve conversion
conversionroom.blogspot.com
conversionroom.blogspot.com
Wasn't there a bit posted here recently about the 'above the fold' placement being a myth ?
And don't place any credit card company logos on your pages without written permission from them, doing so without such permission can cause your merchant account to be yanked.
Now when people talk about it, it's just referencing prominent placement on the site; there's no longer an assumption that users won't know to scroll down, just an assumption that important stuff should be seen first.
But if you look at them carefully, while Amazon is willing to make people scroll for content they don't make you scroll for the picture or the purchase button. Given how much A/B testing they do, I would assume that they have real data for those choices. So while you can put a lot below the fold, there does seem to be value in having certain things above the fold.