For anyone who is interested I pulled the following places used by the F1 championship off Wikipedia

Tourist Trophy, Isle of Man, Vila Real, Portugal; Ulster Grand Prix, Dundrod (Northern Ireland), Dutch TT Assen (Netherlands);, Brno (Czechoslovakia) Zolder (Belgium) , Montjuich (Spain); Hockenheim (Germany), Misano (Italy); Jerez (Spain); Imatra (Finland); Hungaroring (Hungary); Sugo (Japan); Donington Park (England). Kouvola (Finland); Pergusa (Italy);

Not sure how many of these would be still in use or considered road circuits (barring the obvious).

Sam