Arduino fan troubles

How can you connect a DC fan/airblower to an arduino, and program it to spin for 5 seconds, then stop for 5 seconds, the spin for 5 seconds, the stop for 5 seconds. You get the idea.

Our code is below, however it does not work, it however does upload, but nothing happens

int fan = 3;
int a = 9;
int e = 0;

void setup() {

pinMode(a, OUTPUT);

}
void loop() {

e = analogRead (fan);

analogWrite(a, e /4);
}

PLS HELP U R OUR ONLY HOPE!!!!!!!!!!!

i doubt an I/O pin on an Arduino can provide sufficient current for a fan. Have you considered using a motor driver circuit. a higher power transistor would be sufficient (do a google search for such a circuit)

You are reading a pin but have not declared an input in your setup.