Ubuntu 12.10 was released last month with the Amazon shopping lens enabled by default. This was met with much criticism (even EFF raised its concerns) mainly about how user data is being handled or submitted to Amazon and other 3rd parties. While most of the issues have been addressed, the lens is still on by default. So if you search dash, you may likely find the Amazon results too, along with local files, apps and video results.
Developer Mark Tully has created an alternative shopping lens for Ubuntu which shows how Canonical should have implemented the shopping lens without attracting negative criticism. This lens, instead of showing the results in default search results, shows them in a separate dedicated lens. So if you need to search something in Amazon from the desktop, just hit the super key and navigate to shopping lens, and start typing your key words. This way your local searches stay local and no such data is sent to Canonical or other 3rd parties.
To install this lens, you need to add a PPA. Run the following commands in Terminal:
sudo add-apt-repository ppa:markjtully/ppa
sudo apt-get update && sudo apt-get install unity-lens-shopping-alternate
sudo apt-get remove unity-lens-shopping
Not only it shows the results in a separate lens, but also it creates different categories, like books, products, music etc. which makes shopping experience what it should be.
Note: In order to not see the results from Amazon, all you need to do is to navigate to privacy settings and disable online search results. You may also uninstall amazon search lens if you need a permanent solution.