Google this week updated their tool that can be used by you to request removal of links from Google search index of content hosted on third party sites.
This comes handy when Google still has content in its index that has been updated or removed from the web. It might take a few days or even weeks before those indexes are updated.
Google of course requires the content to have updated or removed for this functionality to work. For removed content, the link has to return a proper error response. For updated content, you need to provide a keyword that existed before and is no longer present on the URL.
This tool is useful for removals on other peoples’ websites. You could use this tool if a page has been removed completely, or if it was just changed and you need to have the snippet & cached page removed. If you’re the webmaster of the site, then using the Webmaster Tools URL removal feature is faster & easier.
You can start here: https://www.google.com/webmasters/tools/removals