Spotlights as drl (simple wiring) r56

I want to buy some halogen spotlights and wire them up so they come on with the engine and act a daytime running lights, also adding a relay to the side or headlights so that they turn off when they are on.
Is it a matter of splicing a relay into the headlamp wire or is it more complex on modern cars with the bus?
Thanks for any help available.