The Decemberists, the Wallflowers, Deathcab for Cutie, Semisonic. They all have a melancholy alt-rock sound.

Set It Off

Perturbator, Sopor Aeternus, Fleet Foxes, Goldfrapp, Desire (hard to find, search “mirror mirror”), Meme (has nothing to do with memes, go to mememusic.bandcamp.com), Studio Killers, Savlonic, Ween, Echo and the Bunnymen, Die Antwoord, Death Grips, Jimmy Durante, Kurt Vile, Lifelike, Steve March-Torme...
I can go on forever. These are great to start with.

Pantera - Cowboys from hell
Jinjer - I speak astronomy
Trepalium - Moonshine Limbo
Extreme - Get the fuck out
Tocornal - Shake it
Anderson Paak - Come Down
Stevie Wonder - Superstition
Hank Williams - Hey Good Lookin'
Gojira - Stranded
Mr Big - To be with you
Jungle - Busy Earning
Elton John - Saturday night's alright
Nena - 99 Luftballons
Dion - The wanderer
O'Funk'illo - En el campito
Rage against the Machine - Testify
Wham! - Everything She Wants
Rick James - Give it to me baby
Ice Cube - Check Yo self
Meshuggah - Bleed
Trivium - In Waves
Steve Vai - Erotic Nightmares

Some of my favourite songs. Tried to keep it as diverse as possible

Bohnes: 12 Rounds, Coffins, Aurora Borealis, Slither.
Sickick: Mind Games, Infected, Bermuda.
Grandson: Blood//Water.
Chase Holfelder's Major to Minor series: Blackbird, Every Breath You Take.
TeZATalks: STFD.
Christian Reindl: Nobody Wants to Be Alone (ft Atrel.)
Stromae: Papaoutai, Carmen, Tous le Meme.
Siames: The Wolf.
CAZZETTE: She Wants Me Dead.
Clamavi de Profundis: Song of Durin.
Caravan Palace: Lone Digger.
HitRECord: Mademoiselle Noir.
Daft Punk (Far Out remix): Harder, Better, Faster, Stronger.
The Unthanks: Magpie.
Missio: Bottom of the Deep Blue Sea.
Michael Buble: Feelin' Good.
Pentatonix: Sing. (They also have some brilliant Christmas songs.)
Avicii: Waiting for Love.
Celtic Woman: The Voice.
Erutan: The Willow Maid.
Simon Curtis: Flesh, Super Psycho Love.
Panic! at the Disco: Saturday Night, Victorious, Death of a Bachelor.
Hans Zimmer: At World's End soundtrack.
.
Hope you find something you like on there! I have a fuckton more, if you want more recommendations.

Fleet Foxes - Mykonos

TUUUUUBTHUMPING

Trivium - into the mouth of Hell
Nightwish - Sleeping Sun
Godsmack - When legends rise
Unzucht - Nela
Grandson - Blood // Water
Hollywood Unread - Day of the Dead
Dio - The Last in Line

5 seconds of summer, Arctic Monkeys, The last shadow puppets, Years and Years, Cloves, Jorja Smith, Post Malone, Lana Del Ray, Paramore