Affiliate links can be a problem. Matt Cutts advises that they be run through a redirect script that is blocked in the robots.txt file or simply add the nofollow attribute to each link. I always use a redirect script.
Most of the time, the larger problem with Amazon affiliate marketing is when the content from the Amazon site is used. That is guaranteed to get slapped by the duplicate content filters.
"Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote." -- Benjamin Franklin