Not sure that winamp can work, I don't think so. I would put Quicktime aside, it is not recommended for desktop streaming and if it is Windows you have to do this. At least for the moment, focus on VLC.
Are you using RTSP to playback in VLC? For example if the app is named "live" and the stream is named "myStream"
Code:
rtsp://[wowza-address]:1935/live/myStream
Make sure you are following these guides:
http://www.wowza.com/forums/content....-RTP-streaming
http://www.wowza.com/forums/content....P-RTP-playback
The stream must contain h.264 video and AAC or MP3 audio.
If streaming to the desktop is the main goal, the best choice is Flash RTMP client. You can use JW Player, Flowplayer, or Flash Media Playback (also good for Flash HTTP).
JW Player
http://www.wowza.com/forums/content....a-Media-Server
Flowplayer
http://www.wowza.com/forums/content....a-Media-Server
Flash Media Playback Player
http://www.wowza.com/forums/content....a-Media-Server
Richard