Create a master or main page I want to know how to do is create a master or main page. I come from an ASP.Net background and am truly trying to learn Drupal, but I am very frustrated with finding where/how to start.

For me, the start has always been creating a main page. I use .Net as my platform but usually do all my work through HTML and CSS, as in creating a 3-column website using CSS. However, I really like the functionality of .Net in that I create this on ONE page as a master, and then just insert my content in a content holder. I know things don't work exactly the same, I don't expect them to, but I would like to know how to create a master page, or basically a template that contains the header, footer, menus and content layout.

How do I create a basic main page template?
You may need to do some research into the way the drupal system works. Here is the documentation page for how to theme drupal. http://drupal.org/documentation/theme 

If you are looking to create you own theme. For a beginner, it may be easier to start with a theme framework to mold it into what you want. Here are 3 of some of the more popular frameworks; Zen, Fusion, and Adaptive Theme.

P.S. - You may want to consider doing some basic google research prior to asking questions on here without more supportive information.