I just recently came back from vacation and found all of my contacts deleted. I plugged my iphone into itunes and hit restore thinking my old contacts would come back. I was unsuccessful and it also deleted all of my vacation videos and pictures. Is there any way to undo the restore?! I am very upset!
If you use Time Machine on your iMac, you can restore to the time before you synced your phone. Once that is done, you can restore the phone and when given the choice, restore from your previous backup.
If not there is no other way unless you backed up your contacts.