What do you do when an administartive account is deleted in windows 7

You can create an administrative account, but it will require the old administrator's password to allow you to do so. The customization of the old account will be lost, however.

Did you delete the "Administrator" account? Windows 7 disables the Administrator account as soon as another account is given Administrative rights. So you should have at least two accounts with Administrative rights. Just create a new account and name it "Administrator". You'll have to re-install Windows if you logged off and no longer have Administrative rights.

How did you delete a built in account?

You can't delete the built-in administrator account. Please explain in detail what you did.

I assumed he created an administrative account and then deleted it. He did not mention anything about the built-in admin (the one created when installing the OS) and that one can not be deleted, even by accident.
There is a possibility that he is trying to pull our leg on this one, and get a workaround the original admin account login. That would be a no-no on this forum.

My assumption as well, thus the request for detail (not that I expect the OP to ever return)