Wikipedia states that even in the US, right-of-way is to the vehicle from the right, unless otherwise signed. Except if a minor road emerges into a major road.

In holland it's pretty simple:
- If there are signs the signs tell you who has right of way
- If there's a roundabout, traffic on the roundabout has right of way
- If there are no signs, traffic from the right has right of way
- If there's a speed bump between the alley and the road you are driving on, or if it's a driveway from a private property, the through-road has right of way.
- through-traffic has right of way over turning traffic

The rules in Germany and pretty much anywhere else in europe are pretty much the same.