According to the FAQ you can upload one after 50 posts (http://www.blackhatworld.com/blackhat-seo/faq.php?faq=vb3_board_faq#faq_common) but it doesn't tell you how. I'd assume it is in your profile, in the same area where you chose your current avatar.
If you scroll all the way down to the bottom in the edit avatar area, past all the preselectable avatars you will see the upload option...
Note: The maximum size of your custom image is 100 by 100 pixels or 19.5 KB (whichever is smaller).
Use Microsoft Office picture manager to resize and compress the Avatar images or use any other software to do the same.
www.picresize.com
You have the same problem like me, it says in FAQ that you can upload a custom avatar when you've reached 50 posts and been a member for 30 days.
But it seems that there's a problem with that and some users are stuck in the newbie status, like me.![]()