Connect tethered iPhone 4 iOS 6.0.1 firmware 04.12.02

I have an iPhone 4 that I had someone jailbreak for me. This person has jailbroken many of my devices and is very good at it. My problem is getting the program to work on my laptop when I have had to reboot my iPhone. This program is tethered, so I have to hook it up to my computer in order to use my jailbroken apps once it has rebooted. My guy who jailbreaks things for me lives pretty far and we are snowed in (literally!) so I can't get to him. Which download do I use for modem firmware 04.12.02?? What are the steps I take to get my iPhone to work with my jailbroken apps again?