Kong Audio has released Mini DiZi, a free version of ChineeWinds, their Chinese Flute VSTi. Mini DiZi covers Tenor DiZi, Xiao, and some different expression styles to give you a taste of the various Dizi sounds.
Be sure to check out the DiZi tutorial MIDI files (which are designed for ChineeWinds, but also work for Mini DiZi) to get an idea of how a dizi is supposed to be played, just in case you are not familiar with it.