The fan on my MacBook Core Duo was getting louder and louder as it aged, and I was seeing performance problems that clearly seemed to relate to this failure - lengthy hiccups and freezes, and quite a few Grey Screens of Death. That fan had to go, but I kept putting it off because I didn't want to pay a ton to a repair service for what seemed like a fairly simple operation. Enter IFixit's great guides! The fan I needed was out of stock, but I was able to find it elsewhere (sorry guys), but still ordered a #00 screwdriver and a spudger to complete my repair.
I printed out the guide and checked off each step as I worked my way through. Taking my time to try and work slowly and keep track of all the tiny screws, the whole operation took about an hour and my baby was back up and running, the new fan (quietly) purring and keeping everything running well!
The one most important step - that I had a fair amount of success on, but was not perfect - was to KEEP TRACK OF ALL THE SCREWS. I used some small dishes to try and keep them separated by step, but still ended up mixing some of them up. When I finished, I had three screws unaccounted for, but thankfully, I had secured all of the major connections, so I don't think it'll be a huge problem. Next up: The dead battery on my iPod!