If you are looking for a free tool to create a Google sitemap for your Webmaster Tools account, there are a couple of choices for the Windows platform listed below. Unfortunately, it seems that all of the Mac applications available will cost you. If anyone has a free Mac application, please leave a comment with the URL.

Freeware Sitemap Creators

There are also several web-based tools to create sitemaps online. These tools are not platform dependent, so if you’re on a Mac, you’re in luck. Same goes for other OSes. Some of these online tools do come with limitations, however. Many limit the number of URLs that can be included in the file. So, for a site with numerous URLs, I suggest using Google’s new serverside sitemap tool or perhaps buying a more-robust option.

Free Web-based Sitemap Creators