Hi there, I've been reading this thread and struggling for the last couple of days. I was following all of the steps and things were going alright, I was a bit confused on some terminology, but it's beginning to seem familiar. Anyways, I tried flashing my first kernel using the SGS kernel flasher which was supposed to be okay if you were already rooted. The screen went horribly black and white and I couldn't see anything. I think I started to hear (linda?) talking and then the phone shut off. I let it sit for about 10 minutes wondering if I had done anything right. When I tried to turn it back on, it just kept cycling so I guess the bootloaders weren't working. Then I flashed the stock everything back onto the phone thru ODIN except I couldn't find the stock froyo, only the GB one... Now my phone works (sorta) except I have no service and I cant figure out how to root it again. Nothing seems to be working.
TL;DR - Was on Froyo, had to restore to GB phone keeps on having the vibrating error (looping?) and I can't figure out how to get it back to froyo or root so that I can flash a custom ROM and start to get things working again.
Thanks for the guide so far though, it's been VERY helpful, and it got my phone unbricked!