Because of that, I tend to listen to one song on repeat over and over and over again. I don't think people believe me on this, but it's true:
I typically get about 3-5 songs, and just listen to them over and over and over and over again. It drives everyone around me crazy, so I've invested in good headphones. Because, seriously. If you do the math (and I hope I've done it right; I don't math well), then I listened to "Everything is Ending," the top song in my playlist, for nearly 54 straight hours. That's equivalent to listening to one song for more than two days straight with no break at all.
I've not changed up this method in years. The above five songs got me through writing 4 and a half books (with a few others--all with around 400 plays--sprinkled in for good mix).
My goal is to forget about the music. So I get a good song that sits in my subconscious and doesn't cause trouble. But recently I've found a few other things that make the sound perfect while writing.
This website provides free, constant, streaming ambient noise. And not just any ambient noise. It makes the sound of a busy coffee shop--chairs scooting, an undercurrent of indiscernible talk--and mixes it with a rainy, thundery day. It's seriously awesome. It's enough noise to break the silence, but not enough to distract you. Give it a try!
This is an app you have to download--it only works for a Mac, but it's free. And what it does is magic. It makes your keyboard sound like a noisy typewriter. Every time you push a letter, it clacks. When you hit enter, it dings. It sounds exactly like a typewriter, and it's perfectly synced to your writing. I've been using it for a few days straight, and I'm already hooked. Seriously, this is amazing. It's made me want to type, and more, it's made me keep typing--when I hear the silence and no clickety-clack of the typewriter, I know I'm not working.
Give these two things a whirl--they're really great, and they really keep me motivated to write!