Your fave radio station is 106.7. What are the units of this # & what do they mean in terms of harmonic motion?

That is the frequency of the carrier signal, and its units are Megahertz.

Assuming that this is an FM broadcast station that you are referring to, that unit is actually spelled MegaHertz (the internal capital is important) and abbreviated MHz.

Without KNOWING the band the radio station in in, however, the prefix might be different. For example, it is POSSIBLE for a radio station to broadcast at 106.7  kHz (although that is not in a broadcast band) or 106.7 GHz (again, that is microwave and also not in a band) as well, but then I'm over-thinking the question really...

Hertzz is the SI unit that used to be called "Cycles" which gets to the second part of your question: how does it relate to harmonic motion.  A "Hertz" is One Cycle Per Second meaning the radio station broadcasting on 106.7 MHz uses a wave in which the amplitude of the signal 'oscillates' at 106,700,000 times (going from zero to positive to zero to negative and back to zero again) each and every second.