Q: I don't seem to have option to turn on personnel hotspot

The option will only appear if your carrier supports it, if it'snot showing then you will probably need to contact them to check whether they support it, and if they do, whether you are on the correct tariff with them

Your carrier has confirmed that they support it on the iPad - some support it on an iPhone, but not on iPads. If they do support it on an iPad then you should get the Settings > General > Cellular > Personal Hotspot, if you don't then have you checked to see if there is an update available from your carrier : http://support.apple.com/kb/ht1970