I use two wordpress plugins to generate the sitemap. One is Google sitemap generator, the other is Dagon design sitemap generator. The former is more popular, the latter is easy to install and customize.
The benefits with these two generators are tremendous when it comes to internal linking, helping make a site user friendly, and giving a bonus for search engines to crawl.
For the Dagon desgin sitemap generator:
Simply add the following line to a WordPress page (where you would like the sitemap to display):
<!– ddsitemapgen –>
Note: For those of you using the new rich-text editor – be sure to click the ‘html’ button to edit the page source directly. Otherwise Wordpress will wrap code tags around the line which generates the sitemap and it will not work properly.