  Weakly Interacting Massive Particles (WIMPs) are one of the main candidates
for the dark matter in the Universe. If these particles make up the dark
matter, then they can be captured by the Sun or the Earth, sink to the
respective cores, annihilate, and produce neutrinos. Thus, these neutrinos can
be a striking dark matter signature at neutrino telescopes looking towards the
Sun and/or the Earth. Here, we improve previous analyses on computing the
neutrino yields from WIMP annihilations in several respects. We include
neutrino oscillations in a full three-flavor framework as well as all effects
from neutrino interactions on the way through the Sun (absorption, energy loss,
and regeneration from tau decays). In addition, we study the effects of
non-zero values of the mixing angle $\theta_{13}$ as well as the normal and
inverted neutrino mass hierarchies. Our study is performed in an event-based
setting which makes these results very useful both for theoretical analyses and
for building a neutrino telescope Monte Carlo code. All our results for the
neutrino yields, as well as our Monte Carlo code, are publicly available. We
find that the yield of muon-type neutrinos from WIMP annihilations in the Sun
is enhanced or suppressed, depending on the dominant WIMP annihilation channel.
This effect is due to an effective flavor mixing caused by neutrino
oscillations. For WIMP annihilations inside the Earth, the distance from source
to detector is too small to allow for any significant amount of oscillations at
the neutrino energies relevant for neutrino telescopes.
