I'm looking for a tool or service that can spider a web domain with a large number of pages, create a sitemap, and then visualize that map in a way that will help me see, understand and group content (I'm new to the site) Something like a tree-view or other standard Site Map visualizations would be great. I am yet unable to find a tool that does this (I've found plenty of things to spider the site and create an xml file, nothing to visualize it)
Thanks!
The software Gephi and one of its plugins provides exactly the function that you need.