hdparm, as I'm fairly sure you are aware after reading the article, is a utility that allows you to configure your hard drive for maximum performance. Chances are you still have it on your computer. Do a locate hdparm. That should give you the path name to it. Then, to run it. Just type the full path name. Probably something like /usr/sbin/hdparm. Then give it the options it loves and needs. The first option is probably the hard drive. So, /path/to/hdparm hda I'd imagine.
Unless you are running a SCSI hdd. Then it'd be sda. Whether the article works anymore, I believe it would. I can't see any real reason why it wouldn't / shouldn't. It should be fairly easy to tell for sure though by just looking at the parameters of your hard drive using the hdparm command. Oh yeah. You'll need to be running as root to do all these as well.
Hope that helps some.