I would refer you to the many options... but perhaps a look through the
HCL will yield something. In Windows I use a Pinnacle and couldn't be happier, it was a great deal at the time too, and handles DV via Firewire, has an input and output in both RCA and S-video, and the newer models also do component and HDMI/DVI input. Looking at the HCL though, success may be spotty...But then again it may work fine. Other than pinnacle, I can't really give any personal recommendations.
You can try doing a little google though, looks like searching for Linux Capture Card gives a few reviews and success stories, and whatnot.