Please help: cannot center Div

Hello, I'm working on a template for http://rm2k.be . I have created the basic content section, but as you will soon see, I cannot get the main section to line up perfectly in the center. If someone could look at my css (http://sysh.org/rm2k/style.css) and figure out what I'm doing wrong, I would be extremely grateful. Also, if anyone could give me feedback on the colors/and tips that would be great. Thanks.

note: I've tried putting in margin:auto and then text-align:left and whatnot, but it never seems to work with my page. if anyone could change my code and post it so it correctly centers, i would be overjoyed!

Get rid of this in #body

left: 18%;

I do realize i have to do that, its just that if I get rid of it now, the whole thing goes to the left. Does anybody know how to center that after i get rid of the 18%?

Three ways to Center Elements with CSS (in IE5+/Win and other browsers) (http://www.dynamicsitesolutions.com/css/center_element/)