A general description for setting up a web site in IIS is found here. The following might be more useful in some cases.
After you turn on IIS, you end up with a c:\inetpub\wwwroot directory. This is the default web site.
You can start playing around with this default site. One approach is to use the IIS Manager to create a virtual directory under the wwwroot directory. You can access the IIS Manager through the Administrator Tools in the Control Panel:
Control Panel\System and Security\Administrative Tools
You can then edit permissions for the directory and give yourself read write privilages.