For Airtel Customers:
Dial: 121.
It does not give u the direct option of talkin to the CCE.You will be having some automated instructions.what you need to do is, that u have to choose any one option. for eg, if u wanna ask about new schemes; they will give u all the options. ie. by dialling 1 u get a particular option, dialing 2 u get a another one and so on. den at last the recorded voice will tell u dat if u need to talk to the customer care executive, dial 9 and u will be connected to theCustomer Care Executive.