Go to the Universal Official website. Then go to tickets and vacations. Click on Vacation packages and then in the top right corner tickets only. You have to select your departure date - its a bit unclear but your departure date is the day you actually want the express pass ticket. So type in the date you want, press on search and you'll proceed to another page. Push go and then you'll move on to a list which will have all your options (including your FOTL passes).
Print every e-mail you get up because as I say I don't think its all that clear.
Enjoy!