Wow, that's much bigger than I expected. So basically we can only determine the general direction?
With current-generation detectors installed at three stations which is all we can hope to achieve at the current level of funding in the very near future.
More money, more detections at lower energies, better idea where they come from. There are plenty of instruments in cosmology, astronomy, and physics that have already been designed and planned out, but which do not have the funding to be built; Wait 20 years and five percent of them might come to fruition. You could pour trillions of dollars on these problems without running out of novel questions that we've already proposed ways of answering, and novel results from exploratory instruments we've already proposed building. We spend about 30 billion a year on basic science research according to the NSF, spread over all fields. For comparison, the military gets upwards of 600 billion.
We have good ideas about how to make gravitational wave detectors much, much better, but not how to make them much, much cheaper.
> So basically we can only determine the general direction?
10 square degrees is about 0.3% of the full spherical sky.
The Virgo detector, outside of Pisa, is in the final stages of installing its advanced instrumentation. With LIGO+Virgo a source like the first detection, from September (a very loud event), could be localized to a patch of sky about 10 square degrees in area.