American Telephone Sounds

I'm looking for wav files of what an American phone sounds like when it rings - can anybody help me? I'm getting lots of sites for cellphone rings, and a couple of what the phone sounds like when you pick up the line, but none of what the phone itself sounds like when it rings.

You ask why? Because German/European phones sound different and I'm trying to explain how to my co-workers. Because my mom doesn't recognize my phone at home as ringing because it sounds so different (I have to find another ringing tone she likes).