In the past, one of my friends, a closet DJ, helped me create a ringtone, by clipping the guitar strings from a song. He used Gold wave for it. I have never used it personally, but the UI looks promising.
I know a fair number of musicians -- I live in Austin, after all -- and a whole bunch of them switched to the Mac just because they wanted to use GarageBand as they couldn't find anything comparable for Windows.
It's been a number of years so that might have changed, but it shows how highly GarageBand is viewed in the community.