XML-based catalog?

Hi,

I'm used to using SQLServer for dynamic sites, but I need to learn more
about how XML interacts with ASP, and I have a new project that might be
a good place to start. I need to put together an online product catalog,
but don't need the kind of user-friendly content management system I
usually create for that kind of site (I'll be doing all of the site
maintenance). So I thought maybe just using an XML doc with all the
product specs as the data backbone would be a lighter option for this
project.

I've looked around for some source code or demos to get me started, but
can't find much (I need at least three category levels). Can anyone
point me to a good starting resource? [I'm not averse to paying for some
code if it's fully customizable.]

Thanks.