The standard XML sitemap can be submitted to the three major search engines so you don't really need to bother with urllist.txt.
For automatic creation of sitemaps, have a search for scripts that can generate sitemaps for you, or roll your own - I wrote a PHP script for one of my sites to generate the sitemap since the site is mostly database generated.
You can submit an RSS Feed as a sitemap to Google and Yahoo (and maybe Bing), which is useful for frequently updated content such as news/blogs. Plus if your feed is auto-generated (through WordPress et al) then you don't need to manually update it.
There are also Google's extensions to the sitemap format for images and videos - the latter looks fairly complex but if you work through the linked help guide you should pick it up.