How i can now my website position ranking for specific keywords?
example my website is
gusdecool.com and i want to know my position ranking on Google search for keyword
How to do that? or maybe google has service to do it?
Register for Google Webmaster Tools. If the search term is relevant for your site, it will be displayed in a table including its position in the search results.
Google analytics provides a tool for this in Traffic sources / SEO / Queries... This doesn't exactly show you the keywords, only the queries by which your site was found by the visitors or would be clients.