FORT MYERS, FLA--The "Cash for Clunkers" program knocks three to four thousand dollars off the price of a car when you trade in a car that gets less than 18 miles per gallon.

Already, websites are popping up offering to pre-approve or register you for the program.

You should know...it's a scam.

No one has to sign up for the program.

These websites are trying to get your personal information so they can steal your identity.

Some other things you should be aware of:

You don't need a voucher.

The dealers apply a credit at the purchase--which the government reimburses them for.

The law requires the dealer register with the federal government to offer the credit.

The law requires the vehicle you're trading in be destroyed.

So the value you negotiate with your dealer probably won't exceed its scrap value.

The law requires the dealer tell you the estimated scrap value of your trade in, so ask to see that.

Cars bought after July 1st are eligible.

Your vehicle must be less than 25 years old on the trade in date.

You must purchase or lease a new vehicle to qualify.

Your trade in vehicle must get 18 or less miles per gallon.

The vehicle you're trading in must have been registered and insured for a full year prior to trade in.

The program ends on November first or when all the money the government set aside for the program is exhausted.