Hi,
Welcome to the forum.
Please read the first post in any forum entitled how to use this forum.
http://forum.arduino.cc/index.php/topic,148850.0.html
How do you want the strip to react, just change colour and brightness or do colour patterns.
Here is a great tutorial from Sparkfun using addressable LEDs.
https://learn.sparkfun.com/tutorials/addressable-rgb-led-music-and-sound-visualizer
This might help too;
I googled arduino sound modulation leds
Hope it helps.. Tom.. 