  AIMS: Very high energy (VHE; E>100 GeV) gamma-ray studies were performed for
18 active galactic nuclei (AGN) from a variety of AGN classes.
  METHODS: VHE observations of a sample of 14 AGN, considered candidate VHE
emitters, were made with the High Energy Stereoscopic System (HESS) between
January 2005 and July 2007. Large-zenith-angle observations of three northern
AGN (Mkn 421, Mkn 501, 1ES 1218+304), known to emit VHE gamma rays, were also
performed in order to sample their spectral energy distributions (SEDs) above 1
TeV. In addition, the VHE flux from 1ES 1101-232, previously detected by HESS
in 2004-2005, was monitored during 2006 and 2007.
  RESULTS: As significant detections from the HESS observation program are
reported elsewhere, the results reported here are primarily integral flux upper
limits. The average exposure for each of the 14 VHE-candidate AGN is ~7 h live
time, and the observations have an average energy threshold between 230 GeV and
590 GeV. Upper limits for these 14 AGN range from <0.9% to <4.9% of the Crab
Nebula flux, and eight of these are the most constraining ever reported for the
object. The brief (<2.2 h each) large-zenith-angle observations yield upper
limits for Mkn 501 (<20% Crab above 2.5 TeV) and 1ES 1218+304 (<17% Crab above
1.0 TeV), and a marginal detection (3.5 sigma) of Mkn 421 (50% Crab above 2.1
TeV). 1ES 1101-232 was marginally detected (3.6 sigma, 1.7% Crab above 260 GeV)
during the 2006 (13.7 h live time) observations, but not in the 2007 (4.6 h
live time) data. The upper limit in 2007 (<1.9% Crab above 260 GeV) is below
the average flux measured by HESS from 2004-2006.
