I need some help with the HC-SR04's

here is a project that i used sonar: Digitalduino: Ultrasonic Theremin

it has the sonar only code under "Code for Just Reading Sonar Value:"

the sonar reading code is:

//send a trigger signal
  digitalWrite(trig, HIGH);
  delayMicroseconds(10);
  digitalWrite(trig, LOW);
  //receive the trigger signal echo, and calculate cm to the object
  valueSensor= pulseIn(echo, HIGH);
  dist= valueSensor/58; //converts raw to cm, valueSensor/74/2 = inches
  Serial.println(dist);

so you could do:

//the following four lins for each of the A,B,C,D
#define trig 7 //trigger pin on sonar module
#define echo 6 //echo pin
int dist; //how far the object is away from the module(cm)
int valueSensor = 0; //see here, just added this line

const int buttonPin = 2;     // the number of the pushbutton pin

// Variables will change:
int buttonState;             // the current reading from the input pin
int lastButtonState = LOW;   // the previous reading from the input pin

// the following variables are long's because the time, measured in miliseconds,
// will quickly become a bigger number than can be stored in an int.
long lastDebounceTime = 0;  // the last time the output pin was toggled
long debounceDelay = 50;    // the debounce time; increase if the output flickers

void setup() {
  pinMode(buttonPin, INPUT);
}

void loop() {
  // read the state of the switch into a local variable:
  int reading = digitalRead(buttonPin);

  // check to see if you just pressed the button
  // (i.e. the input went from LOW to HIGH),  and you've waited
  // long enough since the last press to ignore any noise:  

  // If the switch changed, due to noise or pressing:
  if (reading != lastButtonState) {
    // reset the debouncing timer
    lastDebounceTime = millis();
  }
 
  if ((millis() - lastDebounceTime) > debounceDelay) {
    // whatever the reading is at, it's been there for longer
    // than the debounce delay, so take it as the actual current state:
    digitalWrite(trigA, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigA, LOW);
  valueSensorA= pulseIn(echoA, HIGH);
  distB= valueSensorA/58;

digitalWrite(trigB, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigB, LOW);
  valueSensorB= pulseIn(echoB, HIGH);
  distB= valueSensorB/58;

digitalWrite(trigC, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigC, LOW);
  valueSensorC= pulseIn(echoC, HIGH);
  distC= valueSensorC/58;

digitalWrite(trigD, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigD, LOW);
  valueSensorD= pulseIn(echoD, HIGH);
  distD = valueSensorD/58;
    buttonState = reading;
  }


  // save the reading.  Next time through the loop,
  // it'll be the lastButtonState:
  lastButtonState = reading;
}

valueSensorX/58; is just for converting to inches