> i wouldn't even want it on an asteroid. . not
>one close enough to us that we could monitor the
>data anyway. . . if we go out to the mid-solar
>system asteroid belt and create a black hole,
>the earth still gets sucked in.

No, it wouldn't, unless you somehow created a whole crapload of matter out of "nothing" (which, admitedly, may be possible in theory).

You could replace the sun with a black hole of equivalent mass and none of the orbits in the solar system would change. 'Course, we'd all freeze to death, but that's a minor point. Even if you converted the biggest asteroid in the asteroid belt into a black hole, you wouldn't change much. It'd be a black hole with the mass of the original asteroid, which would pretty much just go on its merry way just as the original asteroid had. The only difference is that these things are horrific radiation sources once they start sucking in all the inter-planetary debris around them. That might piss us all off a bit.