Just to add a little to Damasvara's excellent description, and to pre-empt his question...
The price of a pc mouse varies widely. From $1 to hundreds. What you need to ask yourself about peripherals is what is the added benefit of having a more expensive mouse.
I would avoid track ball and go optical. They are even cheaper now, and are much more reliable and accurate.
Wired is better for gaming (IMHO) as it doesn't require batteries, can't recieve interference etc. So you won't get fraged becuase your phone recieved a text and your mouse went mental...But if you are using your pc as a home cinema then it can be nice to sit on the sofa and hit play, so wireless is nice. Don't forget, good batteries are a good investement with a wireless mouse, alternatively, pay a little more for a rechargable mouse. :-D
As for makes and models, stick to your budget and buy the best you can within it. I have a Razor, but Logitech are great too.