Turn find my iPad off
In order to turn off Find My iPad you have to have the password to your old AppleID. If you don't you may have to call Apple Support (or go by an Apple Store?) and have them reset the password to that account.

I believe that if you even try and just wipe the iPad it will require that password. No two ways about it you need that password.

Yes it is annoying but if anyone could simply turn off find my iphone/ipad that would negate it as a setting to help you find stolen devices.