@cmcanham,
Post your pictures by uploading the image file to one of the free hosting sites like [url]photobucket.com[/url], [url]tinypic.com[/url], [url]flickr.com[/url], etc....
They will give you a .jpg url after you upload the file.
Take that url and use the above BBCode Editor code...
Code:[img]http://images.nationalgeographic.com/wpf/media-live/photos/000/007/cache/whale-shark_754_600x450.jpg[/img]