Non Delivery of Tablet after making payment 4 months ago

Location/place: Delhi

Name of company/service: Datawind Innovations Pvt. Ltd.

Dear Sir

Reference No. PMA589
I made a payment in respect of Ubilsate7+ (Aakash Tablet) in Feb, 2012 as per the mail sent by the captioned company. the detail of Payment are as under:
Cheque No. 416679
Cheque dated 24/02/2012
In Favor of DATAWIND INNOVATIONS PVT. LTD.
Amounting Rs. 2,999 of Oriental Bank of Commerce.

As per there mail, they will send my Tablet in march but then they mailed me that it will deliver upto 31st May 2012. but till now i hvn’t received anything. Now they are not replying even from their mail.

I dont have any contact no. except there mail id i.e. [email protected]
and the address where i sent my cheque is
Datawind Innovations Pvt.Ltd.
8148,Jubilee Complex,
Sultanwind Road,
Amritsar -143001

I request your goodself to help me out from this situation.