Yes...There is nothing to prevent two black holes from orbiting each other just as the Moon orbits the Earth. So long as they are at a distance of a few dozen times their event horizons, they can orbit each other more or less stabily. If they are much closer, then tidal forced deform them into footballs and they start to emit gravity waves in huge amounts. This causes the orbits to evolve and decay rapidly so that the black holes eventually merge together.
There is some evidence in distant galaxies, that some of their nuclei may in fact harbor two super massive black holes, each a billion times the mass of the Sun, and with a diameter equal to that of our solar system.
You might like to visit the Binary Black Hole grand challenge supercomputing page to see what different groups are doing to calculate the dynamics of a binary black hole system from general relativity. Also see the page of simulations by Jean Luc at the National Center for Supercomputing Activity. The above illustration shows the event horizons of two black holes merging together as they free fall towards each other.
Copyright 1997 Dr. Sten Odenwald
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