Load them up to a website, right click on the image, go to PROPERTIES, then copy the URL, paste it in your message, highlight it, and click the IMG button.
RPGamer
PS- try it with your avatar, like this
Heres the url
http://www.darkbasicpro.com/apollo/images/avatars/wjSarah2.gif
Now you surround it with the IMG take after highlighting.
It has to be ONLINE first

No loading from your computer

I suggest going over to RGT, loading your image from your computer there, then using the URL to paste the image here. Thats what I do.
RPGamer