Question about sound level meter for you tech guys

[bakergeol]

I am a newbie with regards to tech so bear with me. I have a Goldscan 5 PI. Is there a small portable/handheld(e.g. 9v) sound level meter(or spectrum analyzer) that I could plug into my headphone jack to record readings. I have a vu meter(LED lights for a camcorder) that I plug into my magnetometer headphone jack (9V) and it is mounted on my shaft. However, I would like to have the numbers from a sensitive audio level meter and was wondering if there was something digital out there that someone could recommend.

Thanks George