The J.R.R. Tolkien classic is being filmed in New Zealand by Wellington director Peter Jackson, with backing from Hollywood.
The film publicist, Sian Clement, says 15 thousand extras will be needed for the movie, and this weekend's casting session is the first of many.
Aspiring extras lined up in a 40-metre queue and waited for two hours this afternoon to have their photographs and details taken.
Hopefuls spoken to said they would take any role they were offered, but many expressed an interest in playing orcs, hobbits or trolls.
The main roles in The Lord of the Rings have not yet been announced.