Heat the olive oil in a large skillet over medium-high heat. Fry the halibut steaks on all sides until nicely browned. Remove from pan, and set aside.
Pour the wine into the pan, and use a spatula to scrape any browned bits from the bottom. Let the wine reduce to almost nothing, then stir in the garlic, butter and capers. Season with salt and pepper to taste. Let the sauce simmer for a minute to blend the flavors.
Return the steaks to the pan, and coat them with sauce. Cook until fish flakes easily with a fork. Serve fish immediately with the sauce from the pan poured over it.