Aakash tablet yet not got it

Datawind company has introduced aakash tablet long back. I booked my tablet in february with advance payment by cheque of rs 000. It was to be delivered in march but I have not yet got it. Called up many times, but all in vain. It was to be delivered in march, and its july now. Plz do something, either the tablet or money back. Many of my friends also booked it, but no one has got it yet. Vinod shah