I have a 2001 LS430 that have side mirrors that have been failing gradually over the last few years. Now I hear grinding noises and they won't move properly. I decided to buy new mirrors (not genuine Toyota) for about $130 each and install them myself. I had to spend $60 for custom paint from ERApaints.com but they look decent. Here are a couple videos I made of the process.
First, you have to remove the door panel:

Finally, replace the actual mirrors:

I hope this helps someone. I spent about $300 and the dealer wanted over $2000 for the job.

 

Good info! I'm doing the door locks on both front doors next week, and any tutorial on pulling the door panels is always helpful. Fortunately, my mirrors still function as they should.