Do u see the APN (Access Point Name) option for your carrier In the settings to enable celluar data network?
U could download apple´s own "iPhone Configuration Utility" and make /edit your own APN profile and move It to your iPad or take the easy road.
The easy road Is to do this:
1 - Open http://www.unlockit.co.nz form Ipad using WIFI connection
2 - Create your own APN profile
3 - Save it on the Ipad
4 - Install It.