Do you have a new site? How about a site that you have been working on for years with tons of resources, links to articles, images from other sites and more? Chances are you have broken links. This is known as LINK ROT. Once a quarter, we recommend using some tools to track down the broken links. THEN you’ll have to learn how to fix them. Creating a sitemap at the same time you are checking your links can increase your site’s visibility to Google, Bing, Yahoo, Baidu, Yandex etc, and ensures indexing of the web pages that might not be discovered otherwise.
Here are some tools to help you.
http://validator.w3.org/checklink
http://www.deadlinkchecker.com/
http://www.internetmarketingninjas.com/seo-tools/google-sitemap-generator/
http://www.web-site-map.com/
http://www.web-site-map.com/xml_sitemap.php goes wtih: http://www.brokenlinkcheck.com/link-checker.php