..and then Google-maps \"divide the waters from the waters\"
Well, not in the biblical sense but..
I would like to know what options I have in order to verif
It doesn't seem possible with any current Google service.
But there are other services, like Koordinates Vector JSON Query service! You simply query the data in the URL, and you get back a JSON/XML response.
Example request: http://api.koordinates.com/api/vectorQuery.json?key=YOUR_GEODATA_KEY&layer=1298&x=-159.9609375&y=13.239945499286312&max_results=3&radius=10000&geometry=true&with_field_names=true
You have to register and supply your key and selected layer number. You can search all their repository of available layers. Most of the layers are only regional, but you can find global also, like the World Coastline:

When you select a layer, you click on the "Services" tab, you get the example request URL. I believe you just need to register and that's it!
And now the best:
It is not available right away, hey have to process it somehow, but it should work! The layer repository actually looks like people uploaded them as they needed.