In reply to Fredric Lean's post on Sun 2 Mar 2008 :
Fredric, I'm also shooting on the HV20, and my next purchase is for a beachtek adapter and some new XLR mics – but I've found I've got good audio from this combo:
Audio Technica ATR55 Shotgun Mic ($50)
Shock Mount ($20-40)
A bracket to move the microphone away from the camera. ($10)
I don't use wireless mics.
There are two problems with this setup. One, handling noise – even handling the wire connected to the camera – transmits easily. But I've actually found it to get really, really good sound.
Get that setup if you can afford it – don't try to cheap out on the sound, and that actually sounds like the best option.
You may also want to spend $200 on a Samson Zoom H2 to get a second source of audio if you're doing sit-down interviews.
A deadcat/fluffydog will be useful for cutting out wind noise.
With my setup, here's the audio I got.
Outside, w/Crowd Noise: http://vimeo.com/736167
Outside, w & w/out crowd noise: http://vimeo.com/378059
Outside, w/out crowd noise: http://vimeo.com/377215