Does the FCC Know About This?

I have one of those thingies that broadcasts a low-power FM radio signal so that I can play my iPod through my car radio. The key to getting a good sound is setting the device to a frequency that isn't being used by an area radio station (and avoiding frequencies toward the low end of the dial). Here's the problem: I'm not sure there are any available frequencies in the Nashville area, even though, according to Wikipedia, there should be. But in my experience, even those frequencies that are not officially spoken for, at certain times of day in certain parts of town, broadcast country music stations. I would suggest that country music stations in Nashville have become an organism that seeks out and consumes empty FM frequencies. Eventually, the entire radio dial will be full, and the country stations will be forced to feed on other radio formats. You've been warned.