iPhone Family Plan and Conversion of T-Mobile service provider to AT&T

[champvimal]

Hi,

I have 2 questions :

1) I want to buy iPhone 4S for my wife who has arrived in US a month ago. But I would also like to buy AT&T plan so that we both can leverage AT&T service. Can you tell me if there is any family plan from AT&T?
2) My main dilemma is I am currently having T-Mobile Service on my cell-phone (which is not an iPhone) and now want to convert it to AT&T. Can anyone please advise how to do that and if I can do that without changing my mobile number?

Also, if family plan also includes one more iPhone I can buy, can I have the current mobile line on the new iPhone itself?

Please advise.


Thanks,

Vimal