  Motivated by the TeV-scale gravity scenarios, we study gravitational
radiation in the head-on collision of two black holes in higher dimensional
spacetimes using a close-limit approximation. We prepare time-symmetric initial
data sets for two black holes (the so-called Brill-Lindquist initial data) and
numerically evolve the spacetime in terms of a gauge invariant formulation for
the perturbation around the higher-dimensional Schwarzschild black holes. The
waveform and radiated energy of gravitational waves emitted in the head-on
collision are clarified. Also, the complex frequencies of fundamental
quasinormal modes of higher-dimensional Schwarzschild black holes, which have
not been accurately derived so far, are determined.
