however, i'll go ahead and answer it in case anyone who is a premium member (or about to become one) is wondering how to do it.
when you're creating a thread, there's a checkbox for starting a poll (it says like "yes! create a poll!" or something). check it and create your thread. then, you'll be taken to a page for creating your poll, where you can add your topics and voting choices. then after you do that (and hit submit of course), your thread will be made with a shiny new poll.