Nonlinear light scattering and four-wave mixing from N interacting quantum wires are calculated using Green function techniques. Size confinement results in discrete single- and two-photon resonances. The nonlinear signal per wire increases with N for small N, and saturates at large N. Effects of interactions within wires and among wires on the nonlinear signal and the coherence size are analyzed. The shapes of single-photon resonances for small N (quasi 1D) and for large N (quasi 2D) are compared.