  We propose a framework for calculating scattering and bound state properties
in anisotropic two-dimensional potentials. Using our method, we derive
systematic approximations of partial wave phase shifts and binding energies.
Moreover, the method is suitable for efficient numerical computations. We
calculate the s-wave phase shift and binding energy of polar molecules in two
layers polarized by an external field along an arbitrary direction. We find
that scattering depends strongly on their polarization direction and that
absolute interlayer binding energies are larger than thermal energies at
typical ultracold temperatures.
