Don't worry, we were all new at rooting at some point and used step-by-step guides. Okay, so you need these drivers:
http://droidxcon.moregeekforless.com/Samsung_Mobile_USB_Driver.exe
And Odin and the .tar.md5 files from my link.
Odin is a tool Samsung uses to quickly and easily get the Android OS onto many phones simultaneously in their facility; we're using it to flash a hacked Android OS image to just one phone. First download Android Terminal Emulator and Superuser onto your phone from the Market. Open Odin, put your phone into download mode like so:
1) Pull battery
2) Hold volume down button
3) Plug into computer
It should go to a screen with a yellow triangle and something in Odin should pop up. Some COM text or something with a yellow background. In the PDA part of Odin, pick the .tar.md5 and then hit start. Let it do its thing. Once it's done and it says pass, pull your phone off the computer, put the battery in, and you should be taken to the Android recovery; hit Home to reboot to ED1 which is pre-rooted. You'll just need to block OTAs as follows:
1) Open Terminal Emulator
2) Type "su" (without quotes) and hit enter. Hit allow on the prompt
3) Type "mount -o remount,rw -t yaffs2 /dev/block/mtdblock4 /system" (careful here with spaces) and hit enter.
4) Type "cd /system/etc/security"
5) Type "mv otacerts.zip otacerts.old"
6) Exit
Now get out of Airplane Mode and you should be good to go. That last part may not work and you might get the OTA prompt, haven't had a chance to try it, but it won't harm your phone so hopefully it works for you.