Audio Systems: Cheap speakers, cheap speakers, little speaker

Question
I drive a truck and want to get the cheapest little speaker system. I saw a Audiovox VB12 at walmart. it's 300 watts, but i can't imagine having to have an amplifier for it. I don't have one in my car and it has a good little speaker system with 6'1/2" speakers in the back. What would be the cheapest way to install this with a sorry little radio that came in the truck? Hopefully less than $100 total.

Answer
Joshua,

 ok i would like some more infor like what type of truck and if you have a factory / stock head unit .. and what kind of sound you want ... just fill me in as much as you can so i have an idea of what you are running and what you are wanting

thanks