Hello John,
To your original post here:
Eileen is right, but it's a bit of a mixed bag :-) Here is what I am aware of at this time:
Creating voices from "scratch" is quite a hefty process. So this is definitely not your "I'll record it and send it as a ringtone to your phone" sort of thing :-)
You can justify those efforts if you want to produce and sell a super-high quality sound of an accoustic instrument or some vintage instruments. An example for that would be the "Electric Piano library sampled from Chick Corea's own Fender Rhodes" which you find in the shop at Motifator.com. Another great example of sampled sounds come from an artist and producer I really like too; Peter Schips of CMS Sound Design (
http://www.cms-sounddesign.de/index.html#wa-anchor-top).
And there are many more of course, just think of Yamaha's Alpenvoices or the guys at HDS for Oberkrainer music sounds. So in this category, we're talking about sound sampling.
Then there is the other side: Re-voicing. A good example for that is for instance Heidrun you had mentioned. She uses the keyboard pre-set voices. But on a number of occasions, those pre-sets don't sound ideal. So she would re-mix them. That can be a lot of work too, but not as much as in the case from creating a voice from scratch of course. Her re-voiced sounds are typically included in things like her learning packages or registrations for instance. Then she has a section of "Ensemble Voices". Those are re-mixed pre-sets too, but with the added benefit that they are configured and programmed in such way, that they sound like a really good ensemble. I can only recommend to listen to them so you can hear what I mean.
And our dear Eileen too, check out her Web site, she has posted hundreds of nicely re-voiced sounds. And as usual: Everyone has his or her own sound and genre preferences - but because re-voicing can be done anywhere from very little effort to tons of tweaking, you have much more material to choose from vs. sampling sounds.
From the above, you can now get a feel why some of the stuff is free, some costs little and some can be quite expensive. There is lots of work behind voices Yamaha creates for it's MusicSoft portal. Yet the pricing is quite affordable - my thinking is that they can do that through volume - where smaller vendors might not have that advantage. But that's just a guess of mine.
Hope that helps. Cheers, Roland