Actually the key has a transponder chip, so you can go online to buy a blank key with transponder for the year of your car, then you go to local locksmith who has the computer to program the key into your car's computer, they charge 50% of the dealer price. Once they reprogram the new key, the lost key info will be wiped out and it will not be able to turn on the engine anymore.
The keyless entry remote is actually easier, again go to Ebay, find the same model remote, the seller will have a instruction to teach you how to program the remote into the car computer, for Toyota, I has same experience before, I remember it is basically telling you shut the door, push the lock button in certain sequence and the remote will be set.
The transponder key + programming is around 70-90 bucks, the remote is around 15-25 bucks. The dealer normally charge you 200-300
Good luck
