Centering WordPress Theme

Hi,

I’ve just installed a facebook theme on my page and would like to get the tables centered and top menu, I was able to tweek a little on the style and header sheet and got the top menu centered properly but havn’t been able to modify the mainindex like I want it because when I reduce the internet window nothing is centered. Here is my page http://www.cosmido.com/test

Here is the theme I took http://wordpress.org/extend/themes/facebookwb

Any pros tips on center theme?