I talked with the guy in Oregon today from the company. He said that it varies on what type of license. He gave me an example of a song reproduced for 25 - 30 DVDs e.g wedding etc The cost was about $13 total for that type of license. Many of the musicians are current artists as well.
I'll take a look at Digital Juice though as I have not spent any time there. I ahve used Stock20 and have been pleased.