Using Kubrick Theme for AdSense

Hello,

I’m using Kubrick as my theme and trying to add a Google Adsense link unit. I’d like to place it below the header image and just above the first post on my main page.

Can anyone tell me which theme file I need to edit to place the code properly? I can figure out how to add things to the sidebar and to individual pages, but am not sure about inserting the link unit.

Thanks!

Paul