I am not really into ring tones for my cell phone and most of the people I know are not either. I guess if lots of people called me and I wanted to id them from the ring tone I might see a need for them.

A company called Home Phone Tunes has a product called the RingBoxx that connects between your phone and the phone jack in your home or office and plays whatever tune or sound effect you want.

You can set the RingBoxx to play a specific tune, sound for a specific number, or just set it to play through all the tones in its library. The company also says that you can program the RingBoxx to mute telemarketer calls, though I do not understand how you are supposed to know when a number is a telemarketer. Via Home Phone Tunes