turbo sim versus unlockit??

Hi guys I am not savvy as all of you and am lost on APC's and all the techno jargon I was wondering if one of you would have pity on me and give a little know how so I dont turn my 3G Iphone into a brick!!! I bought it unlocked/jailbroke w/cydia and all the usual bells and whistles, i am a poor student so I cant afford the extremely expensive everything included monthly rate, in fact all I could afford was the prepaid sim card and a monthly auto refill should I run out of minutes via T-mobile, now I would love to have access to their T-zones and was even willing to pay the 5$/month but T-mobile laughed at my demand. I saw all the tweaks on utube and everybody has their own techniques but none can garauntee I wont mess my phone up except for this site whom seems to be ahead of everybody else, so heres my question, as I said its a 3g unlocked with 2.28 firmware, I tried the cydia,packages, and t-mobile hack using unlock.com but I lost my tmobile icon (the phone still worked) and Utube was faddind in and out, then I heard of this super turbo sim that you just piggy back to your t-mobile sim and bingo you got T-zones or even edge if its around, can any of you fine people tell me what,where,how I should go about getting my Tzones for free? without sacrificing any other feature??
I would be most appreciative of any replies....peace,,, boulonman