No one takes offense that you think the guide section sucks, it's just that many people would strongly disargee with you.
Okay but now that I look at the guides there isn't one that specifically tells you what you should do.
So... follow this guide to downgrade to 1.1.1.
http://modmyi.com/wiki/index.php/Get...g_OS_X_current
I know it says osx but that is only if you need to activate the phone without att and itunes. When the restore is finished you dont have to activate it again because your itunes will do that for you since you have a fully activated att iphone.
Then once you have 1.1.1 firmware connect to wifi and go to jailbreakme.com in the safari browser on your iphone and let that do all the magic for you. It will jailbreak the phone and install "installer.app" which is the app that most of use use for installing third party apps.
After that you should be set to add apps from Installer.app.
And one more thing, if you want to upgrade back to 1.1.2 you can do that, but in my opinion there is no real need. I haven't yet, and I think the phone works fine with 1.1.1.
I hope that made sense.