Answer:
Remove the back cover and the battery (or the back/battery as some devices are made as a one piece unit) and you will find it under the battery. Some devices will have a slot that it slides into and others may have a tray that it fits in or under, either way you should be able to see at least a part of the SIM card somewhere in the battery compartment. For further information on your specific device consult your owners manual or contact your service provider.