low voltage 1-5 Amp mono amplifier

I have a Radar Detector that has an external audio port, a 3/32 I believe. I hooked up an external speker to it, and hid it in the dash, but it's too damn quiet to really be heard with the radio going. I wanted to build / pick up a small 1-channel 1-5 watt amplifier that would run or be converted to run off car voltage. I've hunted around and found a few minor schematics for simple designs, but just wondered if a product existed.

Any ideas?

that will do the trick for you.

http://www.aaroncake.net/circuits/amp.htm