fun upbeat dancey music: of montreal, men women & children, scissor sisters, city’s finest, crystal castles (techno), peachcake (!!!!!!!!!!), !!! (aka chk chk chk), m.i.a., uffie, be your own pet, jaguar love, blood brothers (the last 2 have some of the same members), britney spears, justice
hip hop, etc:flobots, P.O.S., murs, jurassic 5, fort minor, atmosphere, lupe fiasco, the roots, notorious BIG, ol dirty bastard
reggae/ska/etc: aggrolites, streetlight manifesto, rancid (skapunk), bob marley, slackers, david hillyard and the rocksteady 7, less than jake, reel big fish, the toasters, bedouin soundclash, king django, skindred, sublime
punk/etc: street dogs, flatfoot 56, time again, horrorpops (rockabilly), nekromantix (rockabilly), dresden dolls, (early) A.F.I., rancid (skapunk), against me!, dropkick murphys, flogging molly, choking victim, devil’s brigade, misfits, f-minus, fireworks, lars frederikson and the bastards, society’s parasites, transplants, static thought, u.s. bombs, leftover crack, nerve agents, tsunami bomb, action design(tsunami bomb and action design are both led by the same chick, agent m. TB has unfortunately broken up, and action design is her new project), roger miret and the disasters, dead reckless (broke up), libertines, dirty pretty things, babyshambles (the last 2 include members from The Libertines, who are no longer a band)
folksy music (and lots of other bands i don’t know how to categorize!!): jenny lewis and/or rilo kiley (jenny lewis is in rilo kiley, but she also does solo stuff), conor oberst and/or bright eyes (conor is basically bright eyes, but he has a solo project also), ben kweller, adam green (not sure if i can call him ‘folk’, i’m not good with defining genres, but i absolutely ADORE him), norah jones, cat power, mates of state, feist, fiery furnaces (i’m not a big fan of them, but a lot of people do, so maybe you’ll like them), kimya dawson, moldy peaches, sufjan stevens, tegan and sara, elliott smith, nada surf, elvis costello, the pierces, gregory & the hawk, broken social scene, (broken social scene also produces a lot of other bands/artists), air france, mgmt, my morning jacket, patrick wolf, she & him, postal service, death cab for cutie (the last 2 are led by the same guy, benjamin gibbard), alanis morisette, sigur ros, art brut, bob dylan, billy joel
hope you find something you like haha