Trying to give something back to the Community...
Quite a common question this one and the answer is the best Visio stencils I've found for ConfigMgr can be downloaded from:
http://myitforum.com/cs2/files/folders/configmgr/entry120945.aspx
I’ve added a link to the FAQShop ConfigMgr Downloads Page for these as well to make it easier for you to find them if you need the link in future ;-)
Read the complete post at http://wmug.co.uk/blogs/cliffs_blog/archive/2009/12/08/configmgr-where-can-i-download-visio-stencils-for-configmgr.aspx