You have no idea the vicious, interconnected cycle you've just tumbled into. But you wanted to know, so here goes.
Death Cab for Cutie got their name from the title of a song by a band called Bonzo Dog Doo-Dah Band, also known as The Bonzos. The song appeared in The Beatles movie, Magical Mystery Tour.
The Bonzos began as The Bonzo Dog Dada Band. The first half of the name is a reference to Bonzo the Dog, a British cartoon character. The second half comes from Dadaism, the art movement. Sounds random, but bear in mind that this was a band formed by several art school students.
The Beatles went through many names, including the Beatals and the Silver Beatles, before settling on The Beatles. The reason for all of the beetle variations is that the name was an homage to The Crickets, an influential band (fronted by Buddy Holly) that originally was going to name themselves "The Beetles."
Buddy Holly, was born Charles Hardin Holley. Buddy was a family nickname. Holley became Holly after his name was misspelled on his contract with Decca Records.
Oh, I almost forgot. The Crickets got their name because bug names were in at the time. They thought it was an unused name, but then they found out that there was another band using the name. Dean Barlow & The Crickets. 
This could go on and on, but you get the idea.
Every band has a unique story behind its name. The goal is to choose something original and memorable, but also a name that means something to the band.
Many bands choose names that reference songs, albums, literature, musicians, films, plays, locations, artwork, or anything else that leaves an impression on them.
If ever you want to know the name origin of a modern band, just ask the band on Twitter or Facebook or wherever. Most are so proud of the name they've chosen that they will gladly take you through the history of the band names and why they settled on what they did.Music: