I would like an Avatar, but can't work out how to upload one.

I've found Member Actions > edit Profile > Edit Avatar. But once I get to this page I'm faced with the following :-

No Avatar Specified
Avatars are small graphics that are displayed under your username whenever you post.
Do not use an avatarNote: if you have a custom avatar selecting this option will delete it.

and no option to select use/upload an avatar.

help please!