Apple is celebrating its 10 billionth song download with a $10,000 iTunes gift card prize for the person who does the transaction, and expects the iTunes milestone to be passed sometime this month. A Michigan 17-year-old won a similar prize on Feb. 23, 2006, when the company marked its first billion songs sold on iTunes. He got a $10,000 iTunes gift card, 10 iPods, an iMac and a phone call from CEO Steve Jobs. Apple also marked its billionth download from its iPhone app store last April by giving a 13-year-old a 10,000 iTunes gift card, an iPod Touch, a Time Capsule and a MacBook Pro. The company is limiting entries to 25 a day.