Don't know of any sites, but for the last couple of years we have only got ours through the post office, every time we have looked around the rate they gave was the best, good luck, Ray
This is a bit vague.
Ray btw m&s a re a bit better than the post office check on line .
Lorcan howmuch money are you gonna change?Do you actually want euros in your hand or euros deposited in a bank account?
The best place of all in the uk high street ive been told of are the cheque cashing businesses you see on most city high streets.Pop in ask the rate then compare it online to m&S it will be an easy comparison .
If its big amounts and you use online companies then they dont normally send you euros but credit euros to a bank account for you.
sainsburys travel money is best at moment, and if you do want bigger amount, negociate the rate with sales advisor there, they can do better deal for you.
I have always used Travelex http://www.travelex.co.uk to buy foreign currency because of the online ordering convenience and simply picking up the money at the airport.