Woohoo! I just figured out how to copy DV movies from my videocamera to the computer! I have a PV-GS14 from Panasonic. They sell a super-secret DV cable for $45. I bought a standard 4pin to 6pin Firewire cable for $15 and it works just fine.
My sound card has a firewire port - I plugged it in, then plugged in the camera, and it registered, loaded the driver it needed automagically, then I started the Roxio Capture software that came with the DVD recorders and it saw the camcorder! I set the camcorder to play and the software saw it and took over! I was able to move several short clips from Christmas a few years back, my new apartment, and the old house over to the computer in .avi format.
Quite large. I think I'll move them to a larger drive and set it to be the default target for future projects. By large, I mean that 7 minutes was 1.6 gigabytes. Big. :)
So - you need the cable - it has to be 4-wire firewire on one end, and whatever matches the firewire port on your computer on the other. Usually 6-wire. If you aren't sure if you have a firewire port, best check to be sure. It looks a little like a USB port but shorter and wider, with a peak in the middle bottom. Hard to explain. Google for a picture of a firewire port. It would be on the soundcard near the sound output jacks.
You will also need a program that can read firewire data and record it to the computer - I have the Roxio suite that came with my system, you may have something different or need to get something. Roxio seems to work fine for me. Just be sure it is version 7 or better as that supports the DVD writing parts.