Amazon.com has the Apple Magic Trackpad for $67.99. This trackpad ships for Free, and it:

• gives you a whole new way to control what’s on your Mac desktop computer.
• Swiping through pages on screen is just like flipping through pages in a magazine.
• Inertial scrolling senses the momentum in your fingers as you move up and down a page.
• Nearly 80 percent larger than the built-in trackpad on the MacBook Pro, giving you plenty of room to perform gestures.
• Magic Trackpad connects to your Mac via Bluetooth wireless technology.