  Observed angular positions and redshifts of large-scale structure tracers
such as galaxies are affected by gravitational waves through volume distortion
and magnification effects. Thus, a gravitational wave background can in
principle be probed through clustering statistics of large-scale structure. We
calculate the observed angular clustering of galaxies in the presence of a
gravitational wave background at linear order including all relativistic
effects. For a scale-invariant spectrum of gravitational waves, the effects are
most significant at the smallest multipoles (2 <= l <= 5), but typically
suppressed by six or more orders of magnitude with respect to scalar
contributions for currently allowed amplitudes of the inflationary
gravitational wave background. We also discuss the most relevant second-order
terms, corresponding to the distortion of tracer correlation functions by
gravitational waves. These provide a natural application of the approach
recently developed in arXiv:1204.3625.
