  We consider D-branes on an orbifold $C^3/Z_n$ and investigate the moduli
space of the D-brane world-volume gauge theory by using toric geometry and
gauged linear sigma models. For $n=11$, we find that there are five phases,
which are topologically distinct and connected by flops to each other. We also
verify that non-geometric phases are projected out for $n=7,9,11$ cases as
expected. Resolutions of non-isolated singularities are also investigated.
