I have a weekly radio show on an internet radio channel on Ustream, normally I record it at home and send it to the studio, but once I did a live show. Can’t remember what DJ controller there was, but what they did was having a seperate computer that receives the audio through the mic input and then broadcasts it on Ustream. However, I don’t think you need a seperate computer, if you use Ustream, you could both load VDJ and Ustream, Take a RCA-jack cable, so the RCA part you plug into your dj controller (so look for a dj controller that has that output capability) and put the jack into the mic input on your computer and configure Ustream to broadcast that.