If i remember right... when you make a new thread, there is an option below where you can say the thread is a poll, and the number of options of the poll.
After you write the thread, and click on Submit, if i remember right appears a place where you can write the poll options.
Im not sure if there is the 50 post limitation for polls also... like... there is some things you only can do/have after 50 posts... so maybe creating polls is one of them...