SharePoint User Group UK

I have a heirachical XML file that describes the navigation I want to see, fundamentally it's the organisation structure and the services they offer.

What's the best practice for implementing this in SharePoint? There are in total over 100 nodes, so I don't want to have to manually create all the relevant sites/subsites, plus it can change occassionally anyway, so I'd like to build in some means of being able to update it automatically anyway.

I could write a program to read the XML file and progromatically create sites/sub-sites etc. Is this the best practice? Or do I simply ignore SharePoint's site map based navigation and write a custom navigation control?

I would create a site definition according to the xml file and deploy it. Then I would create a site collection using that template.

Then it's possible to allow the site admins to controll the occational changes through the sharepoint interface.

OK, this seems like a good option thanks.

However, I've been looking thorugh various documentation and it's not well documented. I've found no fully worked examples, and often contradictary advice on what to edit. There's the webtemp*.xml file in the 12\TEMPLATE\1033\XML directory. There's the onet.xml file in a custom directory in the 12\TEMPLATE\SiteTemplates directory, and there's the files in the 12\TEMPLATE\XML directory.

Does anyone know of a reliable source of documentation for creating a custom site definition for a publishing site with several levels of subsites?

Thanks