Yes they will be very light , so a servo like this will work ! thanks ! how many pins does it needs ? (i hope 1 , i hope 1 , i hope 1.... etc..)
A servo needs 1 pin for control, plus ground and power. Here is a howto on using servos: http://makeprojects.com/Wiki/Servos
You might be able to control a small hobby servo powered by the 5v pin on the Arduino, but as you get to more than 1 servo, or servos that need more power, you should wire up the servos with external power (make sure you connect the Arduino and external power grounds). Here is a tutorial on wiring up servos: http://rcarduino.blogspot.com/2012/04/servo-problems-with-arduino-part-1.html
Since a servo is 0..180 degrees, I would recommend makng 90 degrees the '0' point, and then you can go from -90 to +90 from that point, by adding 90.