  We study the formation of electron-hole pairs for disordered systems in the
limit of weak electron-hole interactions. We find that both attractive and
repulsive interactions lead to electron-hole pair states with large
localization length $\lambda_{2}$ even when we are in this non-excitonic limit.
Using a numerical decimation method to calculate the decay of the Green
function along the diagonal of finite samples, we investigate the dependence of
$\lambda_2(U)$ on disorder, interaction strength $U$ and system size. Infinite
sample size estimates $\xi_{2}(U)$ are obtained by finite-size scaling. The
results show a great similarity to the problem of two interacting electrons in
the same random one-dimensional potential.
