It is best to work out with the dealer you bought the car to get another from them for free. Or contact Toyota service for a new key. If the dealer going to charge you for another key, be prepared to pay $200 and above for each key.
Another option is to buy uncuto key from eBay for 2010 Camry for about $50, go to your dealer and have it cut for $5 to $10 with your vin number. You then need to program the remote for your car to recoginize the remote. The eBay seller will send you instructions.