The top-of-the-line iPod music player from Apple Computer can hold four solid weeks of music. But what if you just want a little peace and quiet? As it turns out, Apple sells that too - sounds of silence for 99 cents. Steve Halberstadt of Raleigh, N.C., made such a purchase last week after discovering that Apple's iTunes store, the Web's leading downloadable music outlet, had added "The Whitey Album," a 1995 release by Ciccone Youth, a jokey side project of the rock band Sonic Youth. The album's second track album, "Silence," consists of 63 seconds of exactly that. (The band...