It has to be less than a certain size, (a jpeg with 800x600 pixels is usually just about right) so if you tried to attach it and couldn't, you may have had a file that was too large.
If you didn't get that far, post a reply to this message (not by writing in the box at the screen bottom, but by hitting the "reply" button) and go down to the box which says "browse" next to "Filename." Find the file that you want to post, and hit "open" in the popup file window. Then, hit "add attachment" in the reply page and wait a few seconds or minutes. When you've done this, hit submit. If it doesn't work, your file is prob. too large.
In the meanwhile, what does the plec look like? Spotted, striped, spiny, bushy? Looking forward to a pic!