iphone-hacks.com

Everything is working fine and it was pretty easy to do.  I just took tutorials from different places and got them to work easily.  I'm running firmware 1.0.2 though, but you can do everything 1.1.1 can but without the itunes icon and easier. SET AUTO-LOCK TO NEVER, before you begin.
1) downgraded to 1.0.2 using ibricker 0.91, very easy.
2) d-loaded and put files from (SAVIOUR) to appropriate places USING IBRICKER (click on files) AGAIN.  (get google help as I do not know how to post links).
3) used IBRICKER to upload BSD and Mobileterminal ONLY.
4) downgraded the baseband using MOBILETERMINAL  ***NOT***  SSH(still can't get it to work).  Again google for the downgrading baseband instructions.  IMPORTANT  CASE Sensitive, so if you see a capital use one.
5) Your phone should now be READY to be unlocked.  Just check your firmware and baseband versions under setting>general>about. 
6) Now turn on IBRICKER again and uplaod anysim 1.0.2 .
7) Run it with your ORIGINAL AT&T sim still in the iphone.  Scroll all the way down and select unlock my phone.  Let it do it's thing for a while.  A message should pop up on the phone saying Unlock Sucessful.
8) Now turn your phone off (with red slider).  Take out the AT&T sim, and put in your T-Mobile Sim.  Turn your phone back on.
9)  Yay!  You should be ready to rock and roll!  Hope this helps at least 1 person out there.  If so, then I'm happy!

THIS WORKED FOR ME AND PLEASE DON"T HOLD ME RESPONSIBLE IF SOMETHING GOES WRONG WITH YOUR PHONE.  ALSO, I AM NOT TECHNICAL AT ALL, JUST FOLLOWED INSTRUCTIONS, SO PLEASE DON"T ASK ANY SUCH ?'S, AS I WILL NOT BE ABLE TO ANSWER THEM.

feel free to edit if needed,  this is my 1'st guide(?), and just want to be helpful, for all you guys have done for me.