A couple weeks ago, I went to see Peter Murphy live. You probably don't know who that is, unless you (a) were alive in the 80s and (b) cared about moody modern rock like Bauhaus, in which case you know that Peter Murphy was Bauhaus' lead singer and has had a fairly successful, if underground, career of his own after the band broke up.
Anyway, the concert was awesome.
But the relevant part of all this background is that quite a bit of Peter Murphy's material is on the soundtrack I made up for The Book. I don't know when The Book and Peter Murphy became inexorably intertwined in my mind, but it happened a long long time ago, and it's irrevocable now. They're so connected that, if certain Peter Murphy songs come on my iPod when I can't write, I have to skip them. They've become evocative of The Book for me, which made it particularly weird and cool to go and see those songs performed live.
I'm sure I'm not the only one who does this (in fact, Stephanie Meyer has soundtrack lists on her webpage, to which I say COPIER! :) ), but it's an indication to me that certain projects are working, percolating, when a soundtrack starts forming in my mind. The TNP, for example, already has a soundtrack that consists, in part, of several songs off the Blaqk Audio CD, which just screams Main Character to me. (By the way, if you like 80s club music like Depeche, you won't go wrong with Blaqk Audio--check it.) Anyway, it's not something that I consciously plan...I don't sit down and think "hmm...what songs would Main Character listen to?" I suppose I could, as a character development exercise, but it's never occurred to me until just now. Songs just start falling into place when I think about a character or a plot line.
I don't pretend to offer a lot of helpful tips on this blog*, mostly because I don't have a lot of helpful tips to offer, but if you already use music to help you with writing, I recommend Pandora, where you can "seed" a radio station with a single song that your character likes, and Pandora will play a bunch of other music based on that song. Then you can pick the songs you want to keep and get rid of the songs you don't want. I've got a personal Pandora radio station (which has led me to a bunch of new songs for Ye Ole iPod), and Pandora stations for each of my projects. I often leave it on in the background while I write, and it always surprises me what the station will recommend and sometimes I think "oh, Main Character would so listen to this band!" and that's fantastic.
*For actual helpful tips, I recommend Lynn Viehl, who writes more than anyone except maybe Charles Dickens, and JA Konrath, whose advice I will certainly be taking once I actually get a book published.