While playing around w/ the sharepoint 2007 beta 2 I couldn't find any option to create a site template from an existing site like there is in v2. After doing some splunking around I found that the following url...
http://yoursiteurl/_layouts/savetmpl.aspx
will take you to a page that lets you save the site as a template. I've saved/restored several sites and it seems to work fine. The only time I have run into problems is when attempting to restore site templates to a different site collection. Be warned there is probly something wrong/missing from the templates it saves or I think MS would have included a link to it from the admin page.
If your really lazy and dont like to remember URL's you could make a feature that installs a link to the 'save as template' page on the site settings page.
-Mark