Many webmasters make money online by promoting Amazon products. You wouldn’t want to link to products that are not available anymore though. Check Amazon Links for WordPress is a handy plugin that lets you know which products are out-of-stock.
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Check Amazon Links helps you find possible errors in your affiliate links to avoid leaving money on the table. It parses your posts and pages for Amazon links and notifies you when products you have linked to are out-of-stock. The script retrieves and displays affiliate tags for each link.
This plugin uses the Amazon Product Advertising API to grab data from Amazon. It supports WordPress Multisite networks. You can try the Check Amazon Links plugin for free.