Help adding multiple blogs / content areas on a page
You define new block regions in your theme, and structure your page.tpl.php to print the regions in the desired structure.  You should look through the theming tutorials

If that is the layout for a single page only, you might want to look into Panels, though be warned that there is a bit of a learning curve.

For styles of blocks, you can override the default CSS in your theme.  Your theme's CSS files will load after the defaults, so it will take precedence.