You can post images by uploading your photo to your own website/hotmail photos/flickr/redbubble/photobucket or any of the other photo places on the net. You then open your photo on the site you have uploaded it to and right click - select Properties - then copy Address (URL) which could look anything like this - http://public.bay.livefilestore.com/y1p ... wept48.jpg
You then make your post to the forum and where you want to add your photo you paste the URL that you have copied, then highlight it and click on Img in the row of boxes above.
Hope this helps