If you have a external domain site, there is a lot of free sitemap generators which help you create a sitemap file. Then upload it to the root of your website and call it sitemap.xml. The URL for the sitemap will be something like http://yourdomainname.com/sitemap.xml. But if you are using blogger you can't upload files to the root directory, you can use it rss feed.
http://YOURBLOG.blogspot.com/rss.xml
OR
http://YOURBLOG.blogspot.com/atom.xml
Add Blog Sitemap to MSN
MSN doesn’t have a address where you can submit sitemaps to but you have to logon to Webmaster Portal where you can create sitemaps, submission and ping tools.
Submit Blog Sitemap to Ask.com
Adding your sitemap to Ask is easy too. Just copy and paste this line into your internet browser, replacing the portion in red with the name of your Blog. And remember to change "YOURBLOG" with you blogs name.
http://submissions.ask.com/ping?sitemap=http://YOURBLOG.blogspot.com/rss.xml