Ok, when your looking at the album on photobucket where the picture you want to post is located, you should be seeing thumbnails of the pics. When you put your cursor over the thumbnails, it should "pop open" a new "option window". Hopefully it'll look like this:
If so, we're on the same page, and there's hope!!
The very bottom option is an "image tag" it looks like this "[IMG] file name", just like in the picture above. I'm not sure about Safari/Mac, but firefox and IE both, when you click the text in the "IMG Code" box, it'll highlight, and you can right click copy, or however you copy text using a Mac.
Once you've copied that text, just paste it into the reply box on this forum. easy as pie. Like this:
Now, it won't show the picture until you either hit the "preview post" button on the bottom of the reply box, or the "submit" button. I HIGHLY suggest you preview your post before submitting so you can see any mistakes, and correct them before posting. I hope this helps! If not, gimme a holler, and I'll help as much as I can...