Multiple ads in 1 widget - theme question or not?

I'm not sure if this question is related to theme or if it's a plugin, or general Wordpress. Happy to take my question to the appropriate forum but thought I'd start here

Here is an example of what I'd love to have - see widget of ads in right sidebar: http://ingoodcents.com There are 3 ads stacked on 3 other ads. I can see from Firebug they're using a plugin to make the ads rotate, I'm just not sure how to get ads side by side like that.

Thanks!