To anyone on HOL, I recommend Ministry of Magic, The Remus Lupins, and the Parselmouths, pretty much and Wizard Rock (wrock) band out there!
As for other music, I'm more into YouTubers' music. Luke Conard, ALL CAPS, Alex Carpenter, Charlie McDonnell, Alex Day, Chameleon Circuit (GREAT Doctor Who band, for all you Whovians!) Jimmy Wong, Alex Goot, the like. Out of more common bands/artists, I like Darren Criss, Charlene Kaye, Michael Buble, Ben Folds, Regina Spektor, Lily Allen, U2, Mika, Jack's Mannquin, Kill Paradise, Jack Johnson, Heyhihello, and STARKID!!!! (ANYthing by them- I love their musicals!) etc. Right now the most-played song on my Itunes is "I Believe" from the musical The Book of Mormon.
Recently, the most played songs on my ipod are oldies that I've found perusing the internet: Careless Whisper by George Michael, I Need a Hero and Total Eclipse of the Heart (TEotH I found through LeakyCon lol) by Bonnie Tyler, Never Gonna Give You Up by Rick Astley (I know, I know XD), and (I've Had) The Time of My Life from Dirty Dancing by Bill Medley and Jennifer Warnes.