Enable 2-finger clicking.
Press the Control key. Press and hold the Control (Ctrl) key while you click the mouse button.
Open your Trackpad preferences as described above. Under the Apple menu, click System Preferences, then click Trackpad.
Get a Mighty Mouse. Understand that any two button mouse can be programmed to work with a right click. Similarly, some seemingly one button mice manufactured by Apple such as the Mighty Mouse or the Wireless Mighty Mouse can be programmed respond to a click on the right side.
Open your Trackpad preferences as described above. Under the Apple menu, click System Preferences, Services then click Services Preferences.