Once you install the drivers attached to the first post you do nothing else.
ADB drivers are installed when you first plug in your phone to the computer. They were not listed because it is a given that they will be there. Though sometimes they do not get installed properly.
Here is what I did to root:
1. Download the 64bit drivers and installed them (I have the 64bit Windows 7 OS)
2. Downloaded the .zip file and unzipped to my desktop using the extract all button.
3. Went to Settings > Applications > Developement > and Enabled Debugging on the phone.
4. Plugged my phone into the computer and waited for it to come up in My Computer.
5. Opened the folder on my desktop and double clicked the START_ROOT file from the extracted folder
6. Waited
7. Rooted.
8.