If you tuned out on rock music a few years ago because you just couldn't stand to hear another Creed song, it's time to come back to the flock. For too long that giddy sense of digging up buried treasure that comes with discovering a new band was a once-, maybe twice-yearly occurrence. Now, thanks in part to file-sharing and iPods, which have turned even graying rock fans into music collectors again, it's hard to get through the week without making a find. We're in a golden age for pure songwriting, with rare talents like Gibbard, the Shins' James Mercer and Wilco's Jeff Tweedy revitalizing the four-minute pop song and making a case that, in fact, it hasn't all been done before.