Brother, I know that many following Saudi Arabia might celebrate Eid tomorrow (Sunday) in UK (and places in Europe), but fact is that these people are only making joke of Islam and fighting Allah and system of Allah, because it is IMPOSSIBLE to sight Moon today (Saturday) in UK or Europe, because there would be no Moon to sight in sky after Sunset as Moonset today (Saturday) is well before Sunset. Here is time of Moonset and Sunset in London on Saturday (19th Sept 2009):
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Sunset: 7.06 PM
Moonset: 6.51 PM
Even sighting of Moon on Sunday (20th Sept 2009) in UK is almost impossible (if not completely impossible). This is the timing of Moonset and Sunset on Sunday.
Sunset: 7.04 PM
Moonset: 7.09 PM
Another site that can give possible moon sighting areas in world on Saturday is:
Moonsighting.com
Anyhow, from position of Moon, the earliest Eid for Europe and UK should be on Monday, but in reality it should be on Tuesday (that is different matter that people for whom Nizam of Allah is not important but Kings and their spokesmen in Mosque is important, they might celebrate Eid any day these worldly Masters would tell them to celebrate).
[Note: It is possible that moon is there in sky (Moonset is after Sunset) but cannot be sighted due to whatever reasons, something Islam also recognises, but it is impossible that Moon can be sighted if Moonset is before sunset]