Can stolen iPhone still be tracked using Find My iPhone after restoring? My iPhone has just been stolen. The chances of the thief resetting is high but will still be locked to my iCloud.

If they reset it and connects to a Wi-Fi in hope it's not locked to iCloud will Find My iPhone tracking still work?
You can't restore an iPhone which has active Find My iPhone using iTunes.
If the iPhone is restored outside of iTunes, then Activation Lock will be enabled and you can still track the device providing a SIM card is inserted or the device is connected to Wi-Fi.