For the UK there is Britcoin.co.uk which is a free service right now and since bank transfers within the UK are free there is truly no cost. We process deposits usually twice a day.
+1
Britcoin are good guys, go with them.
TradeHill offers Euros and is working on GBP but we encourage diversification and the guys behind Britcoin are trustworthy and in this for the right reasons.
Jered