I have a Logitech wireless laser mouse and after a year or so of use, the left click button would double click every time I tried to single click something. As can be imagined, this gets frustrating very fast. So, being the tinkerer that I am, I decided to open her up and see if it could be repaired. Sure enough, It's a pretty simple fix, if you have some common tools and a teaspoon (edit:a tablespoon) of patience. There are some very small parts involved, so you will want to make sure you ware working in a well lit, clean environment so that any parts that are dropped can be easily found. I have now performed this fix for the third time and decided to take pictures this time to share with others who may find this useful. Each time the repair lasts about 6 months to a year before needing to be redone. I imagine at some point the piece causing the problem will break, at which time the mouse will need to be replaced (unless you're determined enough to try and source parts). Good luck with your repair, I hope this helps.
EDIT: There are quite a few comments about the difficulty of step 8. I would advise that you read through some of the comments for various approaches to completing that part of the repair.