Hi, I'm not sure if you ever resolved this issue, but I am in somewhat of a similar boat.
I returned from the UK with the an unlocked Galaxy Note (GT-N7000).
I have been using Pay As You Go T-Mobile, but only with EDGE as data.
I saw that the Note uses the same frequency as AT&T and figured I could at least get 3G from them. I went into the store and one of the sales people said I need to configure the "internet settings" for my Galaxy Note to have a data connection on AT&T.
He put the SIM card from the Galaxy Note on display and put it into my Note. I got full bars, but there was no little letter (E, 3G, H, etc.)
Is this sales person correct? If yes, how can the internet/data settings be tweaked?
What can be done to use my phone?