Locksmiths have been buying new machines and new computers to make car keys that have to be programmed before they will start the ignition. Car manufacturers keep changing the software and the dealer may be the only one who can make your new car key. At least until the locksmith industry can get the new software.
The key prices can vary quite a bit, so call around before you buy your key. It is not recommended that you buy uncut, unprogrammed keys off the internet. Contrary to what they tell you, most locksmiths will not cut and program these keys.
Make sure you always have a spare key. If you lose your only electronic key for your car, it can cost thousands of dollars for a replacement to be made.