Oh the joy of finding drivers is something I don't miss from my days of being a tech. For those of you looking the TV Tuner/Capture card drivers, look no further than this link. HP TV Tuner Drivers.
The linked drivers will work for any variant of XP (ie: Windows XP Pro, Home, Media Center). If you have Windows 7 installed, sorry to say that you'll have to go with a different card or O/S, as it's not supported by the manufacturer or Microsoft. Windows Update will install the drivers, but they'll be disabled for stability reasons. I do believe the built in drivers will work with Windows Vista, but I did not test to make sure.
The drivers are for the HP P/N: 5187-4378, which is an ASUS manufactured card with a Conexant chip. You can find the part number on the card.