You mean you want a graphics card that has an HDMI output? Or you want a video capture card that can capture a digital HDMI signal?
If it' the output you want, most Radeon 5xxx series or Geforce 4xx series cards have an HDMI output. Just look on the specs of the card, or at the picture, to see if it has HDMI, and then make sure it's compatible with your motherboard. Speaking of which, can you post your system specs?