Post your pictures on a hosting site like Flickr, ImageShack, or Photobucket.
Then link the images here. You can click on the little tree in the menu bar when you are creating or editing text and copy and past the photo's URL into the pop up window. The pop up window will give you a little preview, then click "insert"
If you are having difficulty with with the provided URL's right click on the image you want to post, and select "properties"...> Copy the URL from the properties window and paste that into the pop up window.
![Smile [:)]](/emoticons/icon_smile.gif)