Laserdiscs? I'm not sure I understand what you're trying to do, but if you just want to get laserdisc movies to appear on your PC, you could hook a laserdisc player to the inputs on a TV tuner card. You mentioned outputs, I'm not sure if you meant to say that.
If you're talking about a laserdisc player that connects natively/digitally to a PC, I'm not aware of any such drive. It would obviously have to be external, and laserdiscs are only used for analog video anyway so I'm not sure what it would accomplish.
I think many laserdisc players support being controlled by a PC through the serial port, if you have reason to want to do that.