Amazon Preis Change Notification Toolbar indicates availability of APCN, and will engage Preis Watch in one click.
Amazon Preis Change Notification Service (APCN) watches prices at Amazon Webstore and notifies user if Preis change meets user conditions. Conditions configuration is flexible, and includes prices for new, used, collectable and refurbished Store Items.
APCN Service works for Amazon-affiliate web stores as well.