Please contact your nearest dealer for the initial down payment and then emi options as well, they also help u in getting a loan or car finance. You can follow the site for know about the dealers in your city.
New Tata Nano with EasyShift is available at Rs. 2 lac (Ex-showroom, Delhi), and the final cost depends on the valuation of your car. So, first get the valuation of your car from authorized Tata dealer, so he can give you a final quote for the new car.