My parents had problems with noisy neighbours at Christmas, though it wasn't a party, it was them having work done on Christmas Eve through to Boxing Day (think drilling and hammering almost non stop throughout the day). Dad did go round to talk to them but they didn't care (surprise, surprise) and the police said pretty much the same thing, it wasn't for them to deal with. Of course, it being Christmas there was no one at the Council/EH in for the week so there wasn't much they could do. When they did manage to speak to them, they weren't much help - pretty much just said to note down when it happens.
They did get the last laugh though as the work they were having done turned out to be illegal (messing around with the gas, I think) so they were reported. Not long after that, they were gone (I imagine the landlord was not very happy that they were having the work done).
As for parties, my upstairs neighbours occasionally have very noise parties and, in general, always seem to be stomping around/making noises that I cannot identify. I keep thinking maybe I should say something but I'm a baby I'm not sure if it is them being unreasonably noisy or if it's just the floor or something is making them sound like a herd of elephants, in which case it's not really their fault.
If it's a one off, you might just have to deal with it. If it keeps happening, definitely take it further (even if you have to bug EH into submission).