The 80gb on my macbook, where did it all go?

I've had my macbook since about the fall of 2006,
its worked great since the day i got it, but has started to slow down a lot more recently.
I was wondering if there was an easy fix to try and make some space on my hd.
I installed final cut studio, which took up the majority of my space, but out of the 71 gbs's I had set aside from the regular applications, final cut only took up about 31 gb's maybe, I have about 6 gb in pics, 2gb in video, yet when I look under my mac hd I only have 2.71 gb left
Is there simply just not enough space left.
I'm wondering if there was any exces programs I could clear out
I already went through my hd once and cleaned it up
Thanks,

Jon

Run OnyX (it's free) and use it to clear out old caches, history, and logs.

OnyX 1.9.9 - MacUpdate

You also might want to think about running Monolingual which can remove all the languages you don't use. Just be careful not to remove English. Monolingual is also free.

Monolingual 1.3.9 - MacUpdate

Ever think about installing a larger hard drive? Large HD replacements are modestly priced and are easy to install.

Hard Drives for SATA, IDE, ATA - Notebook Hard Drives, Desktop Hard Drives, Internal and External Options with FireWire, USB2, eSATA and more at OtherWorldComputing.com

Regards.

If you have Garageband installed there could be a few gigs used up there for loops - check /Library/Audio/Apple Loops.

There also could be some files in ~/Library, mine is almost 3gigs and I have no idea why. I should probably sort that out actually.

Use whatsize:

WhatSize (Mac) - Download

Or google it. It will tell you what is taking up space and how much.

thanks for all the help, I was going to upgrade my hd, but I plan on getting a MBP so it will pretty much be obsolete to get it.