I'll help you if you stop referencing irritating TV ad campaigns.When you tried to add the attachment did you go through the whole process? You need to press the "browse" button, find and open the file you want, and then press the "Add the file" button.
You can also insert images into the post if they're uploaded elsewhere on the internet, this is what the IMG function is for. When you click it this will appear:
[img][/img]
with your cursor in the middle. You can paste the url of an image right where your cursor is and it'll appear in your post.
I've posted what I hope is a simple explanation of how you get the url (address) of an image from your website
here.