Newbie Need help

I have three tables


Customer

CustomerID CustomerName Birthdate
1 John Doe 1/1/1970 08:31 AM
2 Jane Doe 1/1/1971 01:18 PM
3 Jon Public 1/1/1972 11:58 PM
4 Jane Public 1/1/1973 07:00 AM
5 John Smith 1/1/1974 08:31 AM
Order

OrderID PO Number OrderDate
1000 ABC123 1/1/2012 01:00 PM
2000 112233 2/1/2012 02:00 AM
3000 XYZ987 3/1/2012 03:00 PM
4000 50000 4/1/2012 04:00 AM
5000 Verbal 5/1/2012 05:00 AM
CustomerOrders

CustomerID OrderID IsShipped
1 1000 False
1 3000 True
3 4000 False
2 2000 True
5 5000 True

And the question is to Provide the SQL statement that will return all the CustomerNames who have never placed an order..!!!