Small angle neutron scattering measurements are made on polyisoprene and polydimethylsiloxane (PDMS) solutions and gels. The polyisoprene solutions contain dense clusters of amorphous polymer whose volume fraction is of the order of 0.01 %. Unfilled uncross-linked PDMS solutions, however, show no long-range structure. Filled PDMS samples are also investigated using contrast variation by solvent deuteration to determine the polymer and filler structure factors. The surface area of the filler thus calculated demonstrates that less than 2 % of the free surface of the filler particles is in contact with polymer. The relationship between scattering results and swelling properties is discussed.