Time between switch closes

Hi, I am new to arduino. I am making a slow turning shaft monitor, about 11 rpm. I am using the state change example for my start. A magnetic switch closes each rev. I would like to measure the time between switch closes. can someone point me to an example that will help me?

Hi,
Welcome to the forum. You can copy a link in your post, for example about that State Change : http://arduino.cc/en/Tutorial/ButtonStateChange

Timing is done with the millis() function: millis() - Arduino Reference
It returns the number of milliseconds in a unsigned long.