I found these two patterns online from "Esperanza Rosas". I had to have the page translated but these are her designs and she has posted on youtube also the video tutorial to make these so go watch them! ^^ Just so you know... the videos are not in English :P so just follow along with the picture if you don't speak spanish.
The nice thing about pattern is that it is somewhat 3D as well from the tail and she shows you how to do this twisted look in the videos. (You have to do the tail by hand not with the hook)
Here is another set of video tutorials to make dragonflys by "Maggie Weldon" she has a whole bunch of free patterns she generously puts out online. Check out these tutorials on how to make dragonflys!
Lastly I found this very delicate pattern for a dragonfly from "mypicot.com" Go to the link to see the free pattern on how to make this! http://www.mypicot.com/patterns/7005.pdf
As always enjoy!