The LoLshield is a circuit board that comes with a library that enables one to individually control a matrix of LEDs. Once you have the correct library installed you can use the code LedSign::Set(x,y,1); to individually choose one led to turn on with your limited number of pins on the arduino.
Instructions on how to construct the LoLshield can be found here (http://jimmieprodgers.com/kits/lolshield/makelolshield/).
For our amplifier we choose to use the O2 NwavGuy amp. For information on ordering and/or constructing follow this link, http://nwavguy.blogspot.com/2011/08/o2-details.html.