This thread has become more of co-dependency group then a "let's kick the habit" group!
Here's a suggestion: unsubscribe to any blogs like "Free Kindle Books and Tips," and don't visit their websites.
The problem isn't the free books. The problem is that they prompt you to visit the store. Daily. Once you're there, you you see that *other* book. Oh, and that one. Oooh, and that one, too.
Anyway, I followed my own advice, and I'm now buying fewer books.