Ya know, it really all depends and sometimes it's a mixture of both. I've worked for a station that had a start up library sent with about maybe 100 titles or less, but we had to add manually cuts from CD's/ mp3's from that point on. Also, been in a situation where the format changed slightly and had to enter in 100+ additional titles off of CD's/ mp3's manually. The CD's are usually discs that are provided by a larger music programming corporations, not necessarily anything you'd pick up a record store or something out of the backseat of your car (though that has been done too). Fully pre-packaged "music-ready" hard-drives available for stations to buy, but in opinion that's a lazy and expensive option though. So, I guess it all boils down to the company's policy and/or management's decision..