Sorry, but the local lottery laws in your state do not allow you to buy tickets online from Powerball.net. Whilst this is somewhat inconvenient the situation is changing all the time, so please check back from time to time in case the law changes as it is in many States.
In the meantime, you can buy powerball tickets from authorized retailers in participating states and they can be purchased up to one hour before the drawing. Ticket sales cut-off times can vary, so check with your local lottery retailer for more information.
