We're constantly working to improve the quality of our search results. If you've found a particular site that's spamming our index, we'd like to hear about it. To learn about what we consider acceptable practices, please see our Webmaster Guidelines.
The best way to tell us about a site that doesn't meet our guidelines is by submitting a Spam Report at https://www.google.com/webmasters/tools/spamreport?hl=en. You can also tell us about spam in rich snippets. Spam Reports are submitted directly to our engineers and are used to devise scalable solutions to fight spam.
We appreciate your assistance in maintaining the quality of our search results.