In this Letter, we present a method for calculating transport properties of molecular conductors using a time-independent scattering approach based on Green's functions with absorbing boundaries. The method, which has been used before for chemical reaction dynamics in a grid basis [Seideman, Miller, J. Chem. Phys. 96 (1992) 4412], is formulated here in an LCAO-MO form within simple Huckel theory and extended Huckel theory (EHT), respectively. Test calculations are for a quasi-one-dimensional atom chain. As a more realistic application, the organic molecules benzene-1,4-dithiolate and biphenyl-4,4'-dithiolate between gold electrodes are studied. (C) 2004 Elsevier B.V. All rights reserved.