NEED: Amazon Text Links Plugin?? (Automatic) any recommendations?

Hey guys,

I've been trying to find a WP plugin that automatically turns in-text keywords into Amazon affiliate links in existing and new posts on my WP site but cannot seem to find one.

I found this one called uContext for Amazon, but I can't get it to work. I keep getting "no matching products found" even for very common keywords such as 'protein'.

Anyone know a good plugin that can achieve this?