Contact your carrier, and if you haven't already done so you should also contact 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.
If you had Find My iPad enabled on it 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.
This site contains user submitted content, comments and opinions and is for informational purposes only.
Apple disclaims any and all liability for the acts, omissions and conduct of any third parties in connection with or related to your use of the site.