before Google changed search algoritms in november 2012, I had a website in 7th positition in google on a keywords searched 50.000 monthly. after that suddenly Google placed me to 70th position and after few days after 500th position. as seo i made change links, web directories, classified ads, articles.I need to know why Google hit me so bad. Someone told me about disavow links and I want to make google disconsider that links. How to do that?
Well there is a very little known tool you can use to find that info. You may not of heard of it as it's only been about since 1998 but if you use it to search for "Google webmaster disavow" you find this useful page > http://support.google.com/webmasters/bin/answer.py?hl=en&answer=2648487