my ipad is missing !!

If you haven't already got Find My iPad enabled on your iPad then you can't. If you had got it enabled then you could try locating it either via http://icloud.com on a computer or Find My iPhone / Find My iPad on another device - but that will only work if it's connected to a network and the device hasn't already been wiped and/or Find My iPad disabled on it.

If you think that it was stolen then you should report it to the police. You should also change your iTunes account password, your email account passwords, and any passwords that you'd stored on websites/emails/notes etc.

No, Find My iPad is the only way that you might be able to locate it

That the iPad is not currently connected to a network. What model iPad was it ? If it's a wifi-only model then it will need to be connected to a wifi network for you to have a chance of locating it

Find My iPad needs the iPad to be online, so it will either need to be connected to a wifi network or, if it's a cellular model, to your carrier's network. Find My iPad is very limited with what it can do.

it connects, locked or not. But when it is switched off it is disconnected.