Can I track my stolen iPhone on iCloud?
and what if they take my sim out
It is possible to track your stolen iPhone on iCloud even if the SIM card has been removed granted files from the device are uploaded to iCloud. iCloud allows data from a device to be stored remotely.
No, if you had a program called find my phone it could have told you where it last was/is. Also if you know the IMEI number you can get the phone blocked from the company it was first purchased from
maybe Find My iPhone is better.(If you have registered it before)