If we ignore Indianapolis in the 1950-60 Indy 500 guise, which we always should, then this is the list:
1. Monte Carlo 9 (63 events held)
Fangio 1950
Trintignant 1955
Jack Brabham 1959
Hulme 1967
Beltoise 1972
Depailler 1978
Patrese 1982
Panis 1996
Trulli 2004
2. Monza 7 (66)
Phil Hill 1960
Stewart 1965
Scarfiotti 1966
Regazzoni 1970
Gethin 1971
Montoya 2001
Vettel 2008
3. Montreal 6 (37)
Gilles Villeneuve 1978
Boutsen 1989
Alesi 1995
Hamilton 2007
Kubica 2008
Ricciardo 2014
4. Osterreichring 4 (18)
Watkins Glen 4 (20)
Zandvoort 4 (30)
Hungaroring 4 (31)
Nurburgring 4 (40)
Silverstone 4 (50)
10. Dijon 3 (6)
Reims 3 (11)
Kyalami 3 (20)
Interlagos 3 (34)
Spa 3 (49)
15. Aintree 2 (5)
Rouen 2 (5)
Anderstorp 2 (6)
Zolder 2 (10)
Estoril 2 (13)
Brands Hatch 2 (14)
Mexico City 2 (17)
Catalunya 2 (26)
Imola 2 (27)
Hockenheim 2 (35)
There are two circuits which have seen debut victors in their only world championship event: Sebring (1959 US Grand Prix, Bruce McLaren's first victory) and Zeltweg (1964 Austrian Grand Prix, the sole win for Lorenzo Bandini).
Magny-Cours never saw a debut winner in 18 events. Of current circuits, Bahrain is on 12; Marina Bay 8 and Yas Marina, 7.
Catalunya saw a first debut victor at the 22nd time of asking: Pastor Maldonado in 2012.