How to add my company logo next to, or instead of the Site Title

How can I add my logo?

I have the image url:
http://d2.fixyourpersistency.com/wp-content/uploads/2013/02/d2-logo.jpg

I just want to use this instead of text? Do I have to go this in editor? That seems like a feature that would already be included considering all the toehr options this theme has