Panasonic Lumix TZ3 didital cameras - AC mains adaptors (Panasonic Lumix TZ3 specific) to charge the cameras' battery whilst in the camera, are available at £66+! which I think is too steep a price. Will a Universal AC adaptor, stepped 3V to 12V, (available @ £20) be a suitable replacement and not "blow" my camera?
I think you'll find that most universal adaptors will adjust its current according to the device either manually or otherwise.
The really big problem you face is actually finding the connector tip that fits the TZ series camera. Panasonic use a specialized socket for power input designed by them.