While I'll be adding a file attachment modification to the bulletin board, which will let people upload graphic files to groups, I would encourage regular artists to find off-site hosting space for graphics.  First off, this will save me money because I'll have to upgrade my plan for higher bandwidth if too many images are downloaded.  Secondly, I plan to limit file size to less than some artists might prefer.

So ideally you'll have your own hosting arrangement.  This is pretty easy to do, and not terribly expensive.  You can register a domain at GoDaddy.com for as little as $9/year, and host for as little as $4/month.  Once you've done this, it's a fairly simple matter to upload your images and link to them from She Grew!