With free indexes, as they were indexed by the World Archives Project volunteers.
1891:
1891 NSW census
1901:
1901 NSW census
Don't get too excited, because these censuses don't list every person. The ancestry information about the 1901 census says it only gives the surname of the head of household, but the ones I've looked at have either first name or initial as well, and the same for the 1891. I like the "remarks" column for the 1891 which sometimes says "filled in wrong"!