Radio stream question

Hi all!!! I do radio stream and use the virtual dj. Before a week i got a mixer (3 input channels, 1 output and 2 mics). What i want to do is: Play music from my pc, compine it with the mic sound (through the mixer) and then send it to virtual dj for streaming. I tried that but i couldn't do anything. The staff i have is: 1 laptop, 1 netbook, the mixer and a mic. Does anyone know how can i achieve this? (with the staff i already have or get anything else if i need to). Thnx very much and hope that someone knows...