On my site I have I-frames that display the content and stuff. I want to add a pop-up, but it's linked in the I-frame...it's not working. How would I do that? my site is: http://www.lemonlime.us/vici0uskitty if that helps. (i want to add a pop-up showing a picture.)

Should work fine, you just need to add the popup codes to the page(s) that appear in the iframe...