  LS I +61 303 and LS 5039 are exceptionally rare examples of HMXBs with
MeV-TeV emission, making them two of only five known or proposed "gamma-ray
binaries". There has been disagreement within the literature over whether these
systems are microquasars, with stellar winds accreting onto a compact object to
produce high energy emission and relativistic jets, or whether their emission
properties might be better explained by a relativistic pulsar wind colliding
with the stellar wind. Here we present an attempt to detect radio pulsars in
both systems with the Green Bank Telescope. The upper limits of flux density
are between 4.1-14.5 uJy, and we discuss the null results of the search. Our
spherically symmetric model of the wind of LS 5039 demonstrates that any pulsar
emission will be strongly absorbed by the dense wind unless there is an
evacuated region formed by a relativistic colliding wind shock. LS I +61 303
contains a rapidly rotating Be star whose wind is concentrated near the stellar
equator. As long as the pulsar is not eclipsed by the circumstellar disk or
viewed through the densest wind regions, detecting pulsed emission may be
possible during part of the orbit.
