Ok, had to go searching high and low to figure out how to get avatars here.  Basically, it’s not stored locally.  Instead, you  need to set up an avatar here:

Gravatar – Globally Recognized Avatars.

To date, since it looks like I’m bending the rules of this thing, I can’t set up different avatars for the posters.  Minor detail.  If and when I figure that out, I’ll definitely fix that.