What's the easiest way of editing the built-in ringtones on a Mac? I am not in the slightest bit interested in using tacky song snippets for my ringtones, I want a simple 'ring-ring', 'beep beep', that sort of thing. The ones on the Treo are fine except for two things:

1. Some clocks will only play them once, so I get a short beep then fall back asleep. I'd like to edit a tone so it repeats for (say) a minute.

2. Both when ringing or acting as an alarm clock, I'd like to have the volume ascend from zero to Very Loud.

I think I know how to add a ringtone to the Treo - just save it on a card then browse to it in Blazer, right? But how do I get them off the Treo onto the Mac? How do I then edit them on the Mac (simple edits, as above, so I don't need anything fancy/costly)?

Am I right in thinking that there are two slightly different ringtone databases? My Treo is new, so I'm still learning, but it seems that sometimes I've seen fewer ringers available than other times. Will this complicate matters?