Like many others, I experienced a lot of problems trying to use Logitech keyboards and mice on my Mac. Finally, I sat down and found my own solutions for the problems. I've now collected those problems and solutions on this little site.
It also has some general solutions to problems with keyboard settings, dead keyboard keys, and multiple mouse buttons, which has previously been discussed on Mac OS X Hints, although never solved as far as I know.
I hope it will help others.
Mac OS X Hints
http://hints.macworld.com/article.php?story=2005121610242155