The only way to track your iPad is if you a) set up Find my iPhone on the iPad before it was lost, and b) it is still connected to network and hasn't been wiped out by a thief. There is no way to track it by serial number, although it's a good idea to give that information to the police and your insurance company.
Report to police along with serial number. Change all your passwords.
These links may be helpful.
How to Track and Report Stolen iPad
Reporting a lost or stolen Apple product
Report Stolen iPad Tips and iPad Theft Prevention
How to recover a lost or stolen iPad
How to Find a Stolen iPad
Apple Product Lost or Stolen
Oops! iForgot My New iPad On the Plane; Now What?
If you don't know your lost/stolen iPad's serial number, use the instructions below. The S/N is also on the iPad's box.
How to Find Your iPad Serial Number