Well, I suppose you can take a look at the customer feedback for a particular card on that site. Aside from that, I don't think many people here will be able to help you unless they've just built a new system within the last few months, which is how long PCI Express has been around. You have a mobo with PCI Express slots, right?

Anyway, since it sounds like video capture is important to you, it doesn't look like there are a lot of options out there anyway. Look for which ones do video capture and that'll narrow your search, if that's what you're looking for. Most of these cards have S-Video ports, but those are for video out, not in.