You can target them as soon as you see them. Dont stay to close and you have a very good chance. They move very slowly. But they are difficult to hit. You should always have an officer with Cannon: Scatter Volley I or Beam: Fire at Will I for these situations.. And one finger ready at Evasive Maneuver. Then they shouldnt be a problem.
Yeah, and you need something to get out of tractor beams. Polarise hull is ALWAYS useful.
If you have all of these, the Romulans should be no problem at all... Nada. Remember to laugh at them to **** them off even more, before you destroy them.
You don't need a ton of gear to beat a warbird. All you really need is lots of Har'Peng torpedoes and lots of time. Fly into range, drop a Har'Peng on him, fly out of range, spend the cooldown time shooting down incoming plasma torpedoes. Rinse and repeat.
Never, ever get close enough (I think it's 5KM) for him to pin you with his tractor beam, because then you truly are toast.
It's not a lot of fun. And it takes a while. But it always works.
To be fair, they made warbirds a lot harder with the Rommie FE revamp and you basically can't fight them very successfully if you don't have the right sort of counters (Fire at Will, Repulsors, fighters set to intercept, etc.) And then even when you have the right counters, some times bad things happen, like a slew of unlucky shots.
One other important counter to keep in mind: tractor beams have a range of 5 km. If you can keep your ship further than that from the warbird, distance alone will be your counter. Not that that's easy to do, especially if you're flying a ship that depends upon facing your enemy for alpha strikes...