I don't have any favorite artist, but I do love songs from One Republic and Coldplay. Secrets is my fave for OR and Every Teardrop is a Waterfall is one of my faves from Coldplay.
As for Trance, my roommate listens often to that. There's this song that he plays often, though IDK if its trance or not. I think it was called Tsunami, but it was a remix or something.
My favorite artist has always been Avril Lavigne (since I was like 10). I guess sometimes it has to do with your experiences and relating to music, in a way. I love all OneRepublic songs - especially the songs from Dreaming Out Loud (album). And Idk, Coldplay music just sort of has this nice feel to it.