Avatar in Post using Avatar Plug-in

I would like to add the author's avatar to posts. I am using the Avatar plug-in and it works perfectly for the Comments, but I do not know how to get it to work in the Posts. Can anyone help? Do I need to put some code into the "BYLINE:" sections of the Post/Page Info Items (in Theme Options)? If so, do you know what code? Thanks.

By the way - I am using local Avatars (it's a small family site) - not Gravatars.