Consumer Redressal

i have booked the plot with M/s Octagon Builders and Promotors (P) Ltd. in June 2007 for their Santour Project in Haridwar with customer code is SCH/A/1920 , ihad given them the registraion money along with 1st Installment is INR 145670.00 after that i was not able to give another money for further till that time no plot is alloted in my name , i had asked them to refund my money because i am not able to give furter so please refund my amount but they denied to refund, i had sent a letter to them also with my all details on 11th August 2010 but they have not responded on the same i had contact them so many times and requested for refund till now i have not received any response form them so i need your help to get my money refund.