It took some digging, however:
1990 Japanese GP - 1st: Piquet (Brazilian), 2nd: Moreno (Brazilian), 3rd: Suzuki (Japanese).
2003 Brazilian GP, Jos Verstappen (was ahead of Fisichella when he retired on a similar strategy).
Err... Kimi Raikkonen?
Was it Matt Wilson?
Mathieu Arzeno.
No but he did score on his first rally in a competitive carSebastien Chardonnet?
How do you define "WRC debut"? Are you talking about the driver's first appearance in a WRC event? Or their first appearance in a WRC event while driving a World Rally Car?
Sebastien Ogier. Eighth place at the 2008 Rally of Mexico. Even if it was a J-WRC car.
Abdulaziz Al-Kuwari? (10th at this years Rally Acropolis)