"We are busy updating the store for you and will be back within the hour," a message posted to the Apple Store Web page read as of 11:15 a.m. PST, when it had finally become available.
Apple representatives did not immediately return calls for comment.
Apple CEO Steve Jobson Tuesday during his keynote address at the Macworld Expo in San Francisco. He promised the machine would help further expand Apple's audience beyond the Mac faithful at a price point affordable to most computer shoppers.
Jobs also introduced a tiny flash-memory iPod, which went on sale at the Apple Store on Tuesday in two versions--a 512MB model (enough memory for about 120 songs) for $99 and a 1GB version for $149.
The Mac Mini is a tiny machine with a processor, hard drive and optical drive--you supply the monitor, mouse and keyboard.