Now I juzt started working Integration of Commerce Server 2007 Catalog System with Moss 2007. First we will start with commerce server. Here i am giving few links to learn Commerce Server 2007.
Commerce Server 2007 Installation & Configuration
http://download.microsoft.com/download/3/a/4/3a46267f-9640-4623-86a1-c63bbfea9e1d/Installation%20and%20Configuration%20Guide%20for%20Microsoft%20Commerce%20Server%202007.html
Commerce Server Developers Technical Page :
http://msdn2.microsoft.com/en-us/library/ms864793.aspx
Commerce Server 2007 Virtual Labs from Microsoft
http://msdn2.microsoft.com/en-us/virtuallabs/aa948891.aspx
Commerce Server 2007 WebCasts:
http://dotnetforum.dk/blogs/danske/archive/2006/08/26/Commerce-Server-2007-Webcasts.aspx