If you're doing any shopping in late November this year, and to be real, you definitely are. This is the one thing you can do to make sure you're not getting ripped off. It's really hard to know what's a good deal and what's not.Grab your laptop and get the Keepa Amazon Price Tracker extension. That's spelled K EA. Once installed, the extension provides detailed pricing history for any product on Amazon.Automatically, a chart will appear on every product page showing you how the price has fluctuated over ti ...