Header image option has disappeared

[Moderator note: Topic title de-capped. Please do not shout at us.]

I am trying to create a website/blog and this is my first experience with it. When I first started looking at different themes there was an option under appearances to upload a custom image. That option has disappeared. It does not reappear even with themes that state they support custom images. The box to upload an image is gone regardless of which theme I used.

Seekingthesonsofabraham.com.

I am using Universe right now but have tried twenty ten, twenty eleven, twenty twelve and thirteen, none of which shows me the upload box.