Adding Sitemaps in Blogs and Websites

In a website it´s important to have a SiteMap but does it make any difference in a Blog?
Maybe it does make a difference, in search engines results. If I add a SiteMap in my site maybe my content is easily found and added in search results.
Well, this are some of the questions I asked myself after reading some articles that strongly recommend the use of a SiteMap in websites.
After Googling the subject I came across a few articles and a tutorial about this topic. To learn how to submit your blog´s SiteMap to Google Webmasters Tools, check out the tutorial provided by Blogger Aid, in:
http://blogger-aid.blogspot.com/
This tutorial helped me understand a little more about this topic.
Google Webmasters tools page also provides information. I think I need to make a SiteMap for my site, and disclosure too, I haven´t done this yet.