It has a 1/8 inch standard stereo analog output. YOu can connect a headphone or whatever to it. I actually connect a home made amplifier to it (burr brown OP amp) that gives it a 25 db or so fixed gain and really mellows out the tone like a tube amp) and then play it either on headphones or through a regular power ampifier/home setup. I can also play it in my car, which is cool. and also in my office. And everywhere i go.

I don't use winamp for anything but playback. My library is organized as such: artist-album-song. I suppose you could organize it otherwise, but it's adequate for my needs...however my file structure has nothng to do with winamp. Winamp plays m3u files, if that helps you any.
I've never tried foobar (perhaps the name scared me away? )
-akhilesh