A few of you have been a little uncertain because there is no option to add the shirt or book. DO NOT WORRY. Simply increase your donation by the appropriate amount above your chosen reward and when the Kickstarter is complete you will receive a questionnaire asking if you wanted a book, shirt, or whathaveyou and if so which one (what size) etc.
I also added a donation level that is just the shirt at 21 dollars if you prefer!
Thanks for your support!