BTW, if anyone is curious how you could store data on an audio track, there are lots of different ways.
Use a tone-decoder IC such as the NE567 which would output LOW in the presence of the selected tone and HIGH in the absence.
Another way is to use a DTMF decoder IC. The just encode DTMF tones into your audio track. These are designed to recognize 16 different tone combinations, so you could encode 16 different commands this way.
The old-school way would be to use a discriminator circuit (really just a comparator) that looks for a certain amplitude level and sets to 1 on the presense and 0 on the absence. This is how it is done on magnetic media, for example.
A fancier way is to actually use a modem IC. Since a modem is meant to transmit over telephone wires, it is already in the audio range, and the output will be asynchornous RS232 serial already. Older chips will just connect to your serial port. Newer chips have all kinds of nice features like I2C and SPI interfaces, auto-baud generation, and single-chip design to limit the number of support components required.
I have some older modem ICs that I will play around with. It's a bit overkill for this, really, and I probably wouldn't go that route for this if I didn't already have some ICs. A DTMF decoder is more than enough for something like this. I will experiment with both and post details/code separately as it will likely be useful to others (and probably wouldn't think to look inside this thread to find that info!)
Just wiriting code and doing some research on already suggested ideas. Keep 'em coming!