Hi,
Actually any transcriptions that are sold are supposed to also send royalties for the sale to the copyright holder of the song in question, which often explains the price of such.
And yes, there are some folks who are quite gifted at listening and transcribing recordings. We have some of those here in the forum as a matter of fact
However, they use their ears to hear the instruments/notes and then Notation Composer to put the notes in. One very fine example of this procedure is
in this thread here.
One can definitely get better with practice, but like all good things, there is a learning curve involved and just plain old putting time into it to get good.
ttfn,
Sherry