In the Assemby Room (and at the first frame of you animation) choose Insert> Target Helper Object. Select your Camera and choose the Modifiers tab from the Properties tray. Click the + (add sign) and choose Point At. Put 'Target Helper Object' [exactly like that without the ']in the Towards box. Now the Camera will point to wherever the Target Helper Object is throughout your movie. Just place it at the point on your plane that you want in the centre of the Production Frame and group the two together. Then move them about as you wish.