Fork mounted lights are pretty nice, they really do show up potholes and rough roads better than bar mounted lights. Mounting is pretty much standard with dyno powered lights.

There are a couple different kinds of mounts for battery powered lights. One kind screws into a rack mounts (mid-fork or fork dropout). The other kind tightens to the middle of the fork; I understand you need to check this so the light doesn't slide down the fork and jam the front wheel.