Do other Solar Systems have asteroid belts?
Do other Solar Systems have asteroid belts too?
It's really too early to say.
We've seen planets around several hundred actually, other stars in the last 15 years or so, but the mass of the asteroid belt is quite small.
I don't think that you really have the sensitivity to test something that's that small and which is that spread out across the place that you may need a big concentrated planet which is having a gravitational influence on its host star.