I just picked up an iPhone 3G off craigslist for $100! So now I need to unlock for T-Mobile and jailbreak it. It's currently running 3.1.3, has the 5.9 bootloader, and 05.12.01 baseband. I would like iOS 4, 4.1 or the most recent firmware I can do it on. I've been researching it and just don't know what to do! Could someone please provide a tutorial on how to do it? And I'n on Windows 7 BTW.