Google Webmaster Guidelines For Every SEO
Please find the below link that really help for any seo.
it contains the google webmaster guidelines ,If a site has been affected by a spam action, it may no longer show up in results on Google.com or on any of Google’s partner sites
http://support.google.com/webmasters/bin/answer.py?hl=en&answer=35769
Also want some feedback from you ..feel free to comments.
SEO, SEM & SMO Tip & News Update 