There's two parts to not letting this happen. The first is not buying from Amazon. But the second part is actually identifying and using good alternatives. Even if you don't plan to join jaylake and I (and many others) in boycotting Amazon, it's good to know where else you can buy things.
Let's talk about good alternatives to Amazon. Please reply to this thread with any place you have found to be a good place to buy things you might otherwise buy from Amazon. Links to the publisher's direct are always nice, but I'm mostly thinking of retailers with a broad variety of items.
Books: my favorite ebook retailer is Books on Board. Great selection, easy to use interface, easy to buy things for other people. My brother always begs for gift certificates from here.
Movies: absolutely positively Deep Discount DVD
Electronics: Top of the line place to buy is Tiger Direct If they carry it they have the best pricing for it. And they have the best drill-down-identify-exactly-what-I-want UI I've used on any electronic retailer.
I'd love to know if anyone has a good place to buy physical books or music CDs at a discount.