You'r talking about your system dvd's?
Apple may still supply the original restore CDs/DVDs for a nominal fee. Have your serial number and model information available when you call them. You do not have to be the original owner.
AppleCare Support Phone Number: 1-800-275-2273
open 6am to 6pm Pacific Time
Apple Phone Sales 1-800-692-7753
International Technical Support Numbers