If the usb device is being recognised by windows it will appear in the drop down list in the configure plug-in screen.
(Probably called USB audio device)
If it isn't being shown then you need to make sure Windows is recognising it eg does it need specialised drivers.

Thanks for the help so far, but I am still stuck. When I get to the step where my output plugin options are displayed none of them are meaningful to me and when I click configure for each of them I am not offered any choice like USB port 1 or anything that looks what I need to use to send the file to my outboard DAC. Could I get more detailed guidance, I am a total beginner at this.
Thanks!
Dr. Jay

If you want MM to output sound to some other device you can do so via Options > Output plugins > Configure, in that menu there's a dropdown menu to change the output device.

The subject just about says it all. I am running windows Vista and have downloaded some high resolution files ( 96-24) from HD Tracks to my computer but when I open them I am not given any options other than to play them with media monkey. What I want to do is send them to the usb output of my computer which is connected to an outboard DAC of my stereo system but I don't know how to do that. Please help.
Thanks!
DR jay