We present and discuss the results of a search for extremely metal-poor stars based on photometry from data release DR1.1 of the SkyMapper imaging survey of the southern sky. In particular, we outline our photometric selection procedures and describe the low-resolution (R~3000) spectroscopic follow-up observations that are used to provide estimates of effective temperature, surface gravity, and metallicity ([Fe/H]) for the candidates. The selection process is very efficient: of the 2618 candidates with low-resolution spectra that have photometric metallicity estimates less than or equal to -2.0, 41 per cent have [Fe/H]=<-2.75 and only approximately seven per cent have [Fe/H]>-2.0dex. The most metal-poor candidate in the sample has [Fe/H]<-4.75 and is notably carbon rich. Except at the lowest metallicities ([Fe/H]<-4), the stars observed spectroscopically are dominated by a 'carbon-normal' population with [C/Fe]_1D,LTE_=<+1dex. Consideration of the A(C)_1D,LTE_ versus [Fe/H]_1D,LTE_ diagram suggests that the current selection process is strongly biased against stars with A(C)_1D,LTE_>7.3 (predominantly CEMP-s) while any bias against stars with A(C)_1D,LTE_<7.3 and [C/Fe]_1D,LTE_>+1 (predominantly CEMP-no) is not readily quantifiable given the uncertainty in the SkyMapper v-band DR1.1 photometry. We find that the metallicity distribution function of the observed sample has a power-law slope of {Delta}(LogN)/{Delta}[Fe/H]=1.5+/-0.1dex per dex for -4.0=<[Fe/H]=<-2.75, but appears to drop abruptly at [Fe/H]~-4.2, in line with previous studies.