Since Google is the leader of search engines, getting organic search traffic from Google is one of the most important issue of a website’s success. Either your site is targeted to a product, getting organic traffic for that specific keyword can boost your sale a way lot!
Or if you are in blogging, then getting Google visitors for different keywords will help you to increase traffic, Alexa rank as well as Advertisement and other revenue. We all know this right? But the problem arises when your site is being punished by Google for building spammy and unnatural links and your site lies in the bottom of SERP!

Using Google Disavow Tool
At first go to your Google Webmaster tool> Traffic> Links to your site. Here you should see all the site link that Google has indexed for your site. Check the list carefully and if you find any spammy site(s) linking to you then it is the time to remove those links. You can contact the webmaster to turn down those links but this is not effective all the time. Sometimes you might not get a reply for your request, then the final tool you have to use is Google Disavow Tool.
For checking backlinks, my favorite is OpenSiteExplorer which claim itself as the search engine for links! Yap I believe they are correct, as it is so fast and accurate in finding links for a site. Even you will get data for specific page where your link is placed, which anchor text was used, Domain Authority, Page Authority, Number of outbound links and many more.

Moreover you can also reveal the competitor’s data where they are placing links and can analyze how and where they created links to achieve their success. Then you can repeat your success story following the pioneers! If you have a SEOMoz pro tool, you can get access to OpenSiteExplorer and moreover it is free for a full month to use the full version.
Google Reconsideration Request
The worst case is that when you get an email through Google Webmaster tool that your site has made some deceptive practice in building links and it is punished, then there is no other way except to remove those links and ask Google to reconsider your site again! Once you receive this message like below picture, then you need to drop those links either by contacting with webmaster or using Disavow tool.
Once you have done so, you need to submit reconsideration request form. Within few days you should receive a manual spam revocation email from Google if they are satisfied! So if you are also facing the Google’s warning for your site, then you might like to use Google Disavow Tool to get rid of it.