Cheated by Car Dealer

I have been cheated by Car Dealer during purchase of a new car.. I have learnt in the process that other customers have also been cheated by the same dealer, unaware.. Could I get the list of other customers during a certain period from the Dealer to reveal this ongoing cheating.. scam.. How ?? Is there a way to get the information.. The car Dealer company is a 500Crore turnover company..
Dealer Charged cash for Insurance of car and accessories, saying it is their policy to charge cash only as insurance is another company.. When I asked for receipt ? They said this insurance document is showing full amount and this is receip...t as well.. For accessories, they issued bill.. I applied for bank loan also ...through them.. They said Car invoice and Loan confirmation amount, they will give later, once loan amount transferred to their account..

At later stage.. when I checked with the Bank for balance emi's and bank told me about the passed loan amount..only then I learnt about this cheating.. Now the same dealer saying we issue receipt for every cash payment.. Show us the cash receipts.. I intend to go to consumer court but with only one hope if I could contact other Pl. see comment under my first quote.