The apogee/ perigee of 2019-006A, the object likely shot down, was 260- 282 km, pretty low. Some of that debris could be quite a bit higher, but most of it will be lower, and all of it will have a new perigee/ apogee in that range, which will likely be shrinking quickly. It is expected that it will be similar to the debris cloud from USA-193 (Operation Burnt Frost), which had the following debris cloud Gabbard Plot (From Celestrak)(From Celestrak). Note that all debris reentered within 18 months after that operation, and most within a few days. I suspect it won't be quite as energetic, as there presumably isn't as much fuel quick could cause a significant energy event, but it's the best we have for now.
The best place to look would be from Space-Track's new catalog objects not associated with a launch. That data should be available soon. If you want to follow someone on Twitter to find out more, I recommend Jonathan McDowell
Edit: The first Gabbard Plot has been made for this event, from this source. Looks like it is going quite high.