My beloved 6-year-old MacBook Pro finally succumbed to all the travel and abuse I've subjected it to over the years. The magsafe stopped recognizing the power adapter one day, and eventually the battery ran dead.
The Apple folks told me that they don't provide replacement parts for products older than 5 years, but referred me to ifixit.com
Easy breezy lemon squeezy. The guide at http://www.ifixit.com/Guide/Installing-M... covered everything, and she was up and running again in no time.
Two things I noticed:
1) Some of the screw mounts holding the case together had become corroded, and broke off when I removed the screws.
2) Getting the cover off was tricky, as the guide warns. The front part of the cover near the trackpad is attached using snaps and not screws, so you have to force them off.