If you hear clicking, it's a 95% chance that it's shot.
The Firewire thing you're talking about is called
target disk mode. To use it, turn on the computer with the hard drive problems while holding the "T" key. You can then attach the Macbook to any other Firewire equipped computer and have it function as an external hard drive. But since it sounds like the disk has failed, this probably won't work.
You can look at the status of the disk by booting up from your original install disc, going through until it asks you where to install to, then open up Disk Utility. If your hard drive shows up, then click on it and view information about it on the bottom of the screen. The S.M.A.R.T. status will tell you if it's failed or not.
Finally, you can try using an external hard drive cable. This will allow you to hook your hard drive up to an external board and then plug it into another computer via USB. Getting the hard drive out is very simple, you can follow
Apple's guide to removing it. Assuming you don't have an external adapter, you'll want to look for a "SATA to USB with 2.5" notebook drive adapter" one.
Alternatively, you could simply take the hard drive out and reinsert it. It could be that something is in the way of your SATA data connection but not the power connection. I've had this happen before.
I'd only use the SATA to USB adapter means if the Macbook reports that the drive is working, but you can't boot up for some reason. I'm going to go ahead and put all my chickens in the basket and say that it's dead though, in which case you won't be able to recover any data without some sort of
hi-tech, super expensive means. Hopefully that's not the case, but if so, it should prod you to invest in an external hard drive for Time Machine backups in the future.
Anyways, I know that's a lot of information, but hopefully it'll help you recover your data if there's anything left. Losing a hard drive is almost as bad as losing a loved one sometimes.
