When I run across a site that makes my life easier I try to share it with everyone else. The site gpoguy.com is a great site if you need help figuring out windows group policy. The part of the site that stand out the most for me is the free training videos. The videos cover everything from the basic introduction all the way up to doing things at a forest level. There is also a list of free tools for windows group policy that can be very useful. Bookmark this site as I am sure you will fine a need for it during your IT career.
Main Site
http://www.gpoguy.com/
GPOGUY Video Training
http://www.gpoguy.com/Group-Policy-Video-Training.aspx
