TikZ-dependency allows you to draw dependency graphs in LaTeX documents with little or no effort.
The package has a very easy to learn, high level interface that can be used to draw simple dependency trees, complex non projective graphs, bubble parses, and in general any kind of graph that is based on a sequence of nodes and edges among these. It is based on PGF/TikZ and can be used either with latex or pdflatex. It comes with very comprehensive documentation that will get you started in 10 minutes, even without any prior knowledge of TikZ. It also provides a lot of styling facilities to let you personalize the look and feel of the graphs.