Yes, you can use a converter box like the ADS Pyro A/V Link or Canopus ADVC-110 (or any number of others). They all connect to your firewire port and emulate a DV device (like your camera). You can even capture analog video through them. I have an ADS A/V Link and works great.
I don't know what training dvd you are talking about (so it may mention what I'm about to say) but you don't have to use a camera, you could use a convertor like the Canopus ADVC 100.