I have been using magento to create a sitemap. Is this a good tool to use or should I be doing or using something different? How often do I need to regenerate this sitemap?
Do you mean you are using a Magento module to create sitemaps? ... Do you only need normal XML sitemaps? (Not video, image etc.) Does the generated XML sitemap only include unique URLs (e.g. not URLs that point to other through canonical) ... Just recreate sitemaps when you have added new pages.