Sensing vibrations?

Hi to all! I'm very new to arduino, I would like to achieve something like in this video. Here the guy is using a piezo sensor, but not arduino, I would liek to know if this is the easiest way to make it with arduino and perhaps where I can find a similar circuit! Thank you so much in advance :)

You can use the analogRead to get values off the piezo.

I'm doing something similar (not water, but getting piezo input) and have also just started. These two links helped me out a lot.

http://leucos.lstilde.org/wp/2009/06/piezo-transducer-signal-conditioning/

http://www.iua.upf.es/~jlozano/interfaces/blow_sensor.html

I setup a circuit like in the first link, to clean the piezo signal up, then used the code to read when it passes a threshold. This reads the analog input, and lights an LED when it's triggered.

#define LED 13
int val = 0;

void setup() {
  pinMode(LED, OUTPUT);
  pinMode(SOLENOID, OUTPUT);
}
void loop() {
  val = analogRead(0);
  if (val > 50) { // THRESHOLD TO TRIGGER
  digitalWrite(LED, HIGH);
  }
  delay(10); // DURATION OF STROKE
  digitalWrite(LED, LOW);

}