How to get wider Margin & Smaller Text

Where can I find the place to adjust the margins around the main section of the page and also in the side boxes? I can't find it in the stylesheet...
NEVERMIND...I finally found it.

Also...where do I change the size of the text in the main section of the page?

Thanks!

Also...where do I change the size of the text in the main section of the page?
If you are refering to the text that would be yours to replace the main page default text like this
This section of text is from the Define Pages Editor located under Tools in the Admin.
This is done in the admin > tools > defines page editor. Select the html editor and it resembles a word processor and you can style, color, and set the text size.

If this is not it, specify what mainpage text you are meaning