Hi there, depending on whether youl be happy with just the one or if youl be using a few... have a look at the nissin di622 and di866 (the mark 2 versions)
theyre about £110 and £180 new respectively.
ive been having a look around for my 550d and if youve got the cash.. the di866 sounds like a very very good option. if your budgeting, the di622 appears a safe bet.. you can get 2nd hand 622s for about £60 but there are few of them and even fewer 2nd hand di866's
Re canon flashes - if youve got the money then fair enough, but they are way too expensive for me
hope that helps,
Pete : )