Its really difficult to find the appropriate parts for the ornithopter.. I am strucked with my build and will be completing it soon as i got some new ideas and managed some parts...
First study about them well and then start making them..
This is my build
http://www.rcindia.org/kites-trains-free-flight-and-all-others/rc-ornithopter-homemade/And refer rcroups.com/ornithopter for many many designs by doctor Kazu kaku, He is a very very nice guy and will help you for all your questions..
Feel free to contact me also, If you need any local help