Euro do the coils for £25 each, Wazzer is bang on though, check with the dealer weather your car is on the recall. Keep the old coil pack as they will only replace original coils.
No the ARZ doesn't have one. You should check if your car is part of the recall with VW
If it's any consulation I'm having the same grief with my 02 plate and I've replaced the plug just in case... No change!! Did your engine managment light come on and does flash on/off when driving??