From their website:
Pre-sale ends here, Wednesday April 27. Orders ship mid May 2011.
Deal contains the new 64 page expansion book and all 12 new miniatures: 6 Sturmzombies, Blitzhund MKII, Bazooka APE, Drohne, The Hurricane, the massive Panzeraffe, and the truly massive Gracie. Retail price on all this is $138. The pre-order special gets you the whole shebang for $110 and gets your stuff shipped to you at the earliest possible moment.
If you are in Europe, get it from West Wind. In Oz/NZ, get it from Little Soldiers. Both will be putting this deal up within the week.