Here are two sites for you to have a look at:
http://www.submitexpress.com/metatags.htmlWith this free site you can either check or generate html meta tags.This also free site generates .xml sitemaps which are used for the Google search engine:
http://www.xml-sitemaps.com/To my knowledge, sitemaps are the only use for .xml files.Meta tags are always coded in html and placed in the header part of your webpage.Regards, Zyfert
http://xsitepro.cybersprout.com