How can I make my page in three column?

[askme]

Can some one let me know how I can increase the width of my page to cover entire screen, I am running (1024x768).
Now with that resolution, I see blank white space both side of page. I want to utilize this space(like this forum page).

I want to optimize my page for resolution 1024x768, and same time I want to make all pages in three column, so that in one column I can put sub menu (apart from top horizontal menu), in centre my whole page content, while at right (small column) can put some advertisements.

How to achieve that, which pages to modify, what are the codes

You can check my current website

www.eRealMedia.com

[Dr.CSS]

rene :.
thanks for the compliment 
it's a passion of mine that i'm more than happy to share :...