Jeepers, BillD, there are bunches of them on youtube..take yer pick:

HERE, or HERE. And, if those don't got back far enough for you...try THIS ONE.

I don't pay for any extras on my phone, so just have one of the tones which it came with, but when I had an answering machine I could control, i.e. record a whole message, I had a tune, written and producing by Jeri, called "katlaughing!"