BT
Tiesto
Paul van dyk
Filo & Peri
GTR
Iio
Solar Stone
There's some of my favorites at a glance. Oakenfold is alright, his breakbeat stuff is pretty solid, though his true trance is lacking.
With anything but trance especially, everybody puts out a lot of shitty tracks. What separates the good DJ's is that they put out good ones too. So don't get discouraged if one or two tracks aren't that hot.