Hi, 
If you have the Internet Toolkit already, the 
User’s Guide has great instructions that will help you get started.  In particular to your questions, I would suggest you take a look at the section titled “Using CGI in LabVIEW” and “Getting Started with the G Web Server”.  
Also, once you start the G Web Server (Tools >> Internet Toolkit >> Start G Web Server), just type in http://localhost on a web browser and you will be directed to a page with a large selection of CGI examples.  
Again, the Internet Tookit is your best bet.  From there, take a look at the User’s Guide for examples and instructions.  Thanks!
Kileen