Here's the lead singer of The Pixies in a 1989 Dutch television interview talking about his song writing process. Pay special attention to (or skip to) the part about 2:50 in when he describes how the lyrics are the last thing to come to a song, it's only after the sound and structure are well established. And it's true! He's describing his process for Doolittle, an album I love more than I can adequately relate for its crushing beauty.
Also, pay attention to the later parts of the interview - and I do hope you watch the whole thing - because he has such honest, intelligent humility. He just wants to make good enough records that people years later will slap him on the back and say hey, you made a good record. You made more than that, Black Francis.
(found via kottke)