How to include a pic in the post:
1. Host it somewhere. There's lots of image hosting services, here's three of them:
http://imageshack.us/ http://imgur.com/ http://photobucket.com/ Some of them might offer the "Message board link" with the IMG tag right away, you can paste it right into your message.
2. Otherwise, when editing the post, click on the "Insert image" icon (circled in red):
.
Enter the URL in the dialog that pops up. Or you could simply type the IMG tag (highlighted in yellow) with the URL of the image manually.
Done!
Please keep in mind that the images that you want to include in your post have to be shrunk to the width of around 640 pixels, 800 at most. Photos straight from the camera are far too large. Most of the image hosting services allow you to resize the image when uploading it. If you fail to do that people will crack jokes about not having 40" monitors
Preview the message before submitting it to make sure you got everything right.