See how to a a button with Arduino with MAKE Magazine! This is a video tutorial on a favorite little micro-controller, the Arduino. This is a really informal how-to, and is meant to show you just how fast and easy it is to work with the Arduino.
This video is all about connecting a push button that controls the LED. This is the simplest way to use a button. However, it isn't always the best way since it doesn't account for 'debouncing'. Everything you ever wanted to know about the Arduino, including the IDE and USB drivers, can be found at http://www.arduino.cc.