Oh, you can post images, IJ just doesn't have image hosting like LJ does. You can host the images over at LJ in the Scrapbook or on Photobucket or Flickr or what have you, and then post them here.
The html to post an image is: < img src="url of the image where it's hosted"> without the space before 'img'.
Although in this case the target image is really big, so I would post a smaller version which links to the big one, which would go: < a href="url of the full sized image">< img src="url of the smaller image">< /a> Again, the initial spaces after the '<' would all have to go. I've just got them there so it doesn't think it's code and make it go all invisible.