To locate them:
* Look directly on top of the engine: The coil pack is usually a relatively compact black rectangular or square unit. You'll likely see spark plug wires coming out of it, going down to the spark plugs which are in the cylinder head.
* Follow the spark plug wires: If you can find the spark plug wires, trace them back to their source – the coil pack.
The exact location might vary slightly depending on the specific engine configuration (2.0L or 3.0L V6), but they're generally fairly easy to spot on top of the engine. A quick online search for "2004 Ford Escape 2.0L engine bay diagram" (or "3.0L" if you have the V6) with images will give you a visual reference. This will help you pinpoint the exact location of the coil pack and spark plugs.