Q: How to block cell phone from send me iMessage on iPad

there is no way to block a specific sender from within IOS.  you can simply ignore the message, I suppose.

It is is really irritating, change your 'receive at ' setting in settings - but that means nobody else will reach you either unless they know your new contact address.

Click contact on top right

Click info button, "i" in a circle.

Scroll to bottom and

Select block this caller.

Expanding on what pjl said, there's no way to block a sender in iOS 6. If you upgrade to iOS 7, then you will get the ability to block senders in iMessages.

Regards.

varjak paw wrote:

If you upgrade to iOS 7, then you will get the ability to block senders in iMessages.

 

That's good to know. I never knew about that ability in iOS 7. Thanks varjak.

Once you upgrade, see this article for instructions:

http://support.apple.com/kb/HT5845

Regards.