Thanks for reply,
But If my Icloud account is registered with Apple ,means my serial no, of the macbook is registered with my icloud account,in this case even if the new OS is installed,can not Apple locate the device by serail no.?
I am sure Apple is capable but, unfortunately there is no way. Once the Harddrive is wiped you have no way of tracking. You can prevent them using the machine in the future by putting a firmware lock on it.
It would be awesome if Apple built in findmymac into the firmware so no matter what you can track it when connected to wifi