Molecular van der Waals (vdW) complexes A·Mn of A = perylene (Per) and tetracene (Tet) and M = benzene (B), cyclohexane, and CCl4 were studied by using the technique of two-color resonant ionization (2CRI) spectroscopy. The investigations included large complexes up to n = 7. The red spectral shifts of the origins of the complexes relative to the bare parent molecules and spectral features of conformational vdW isomers were determined. It was found that the origin of the Tet·B2 complex is blue-shifted with respect to Tet·B1. This unusual behavior is tentatively explained by assuming a specific interaction of the two benzene molecules adsorbed on one side of the tetracene molecular plane in a π-shape geometry. The red spectral shifts of Per·Bn and Tet·Bn complexes exhibit a saturation for n = 5-7 at ca. 700 cm-1 which corresponds to ca. 50% of the solvent red spectral shift observed in benzene solutions. In analogy to atomic complexation, it is therefore suggested that a "first solvent shell" consists of 5-7 benzene molecules for vdW complexes of perylene and tetracene.