Wasn't aware there was a way to post questions.
Where : http://arduino-direct.com/sunshop/index.php?l=product_detail&p=39
What : Thermistor 103 with a LM358 chip and some resistors.
Code :
int thermPin = A0;
float thermValue = 0;
void setup ()
{
Serial.begin (9600);
}
void loop ()
{
thermValue = analogRead (thermPin);
Serial.println (thermValue);
delay (1000);
}