Is this the photo you want to use?
In User Control Panel, click on Edit avatar,
Check the box that says 'Use Custom Avatar'
Below that use Option 1
Delete the
http:www that is already in the box and copy this URL
http://img.photobucket.com/albums/0903/Garden_girl/CIMG0543.jpg
Works best if you copy from end to the beginning with a live link.
Paste the URL in the box.
Click on save changes at the bottom and you're done.
I would open up a Photobucket account, it's great for posting pictures in the Photo forum.