Hi,
The web.sitemap is a feature of asp.net and it is used by the breadcrumb (SiteMapPath) control, the Menu control, and other controls.
Instead of removing this from the project you should be able to edit your masterpage to just not include the menu control that Beerhouse Starter Kit uses.
I did read this book about a year ago but I dont recall how the pages are laid out.
If you post up the markup for your site where it generates the menu and also a link to this css menu you want to integrate then maybe somebody here will be able to help you out a bit more.