From a SCA mailing list I’m on, in turn from a Lord of the Rings movie site, here is a list of cast members for the upcoming LOTR movie trilogy:

Aragorn:-Stuart Townsend
Arwen:-Liv Tyler
Beregond:-Nick Nolte*
Boromir:-Sean Bean
Bilbo:-Sir Ian Holm
Eowyn:-Mira Sorvino*
Frodo:-Elijah Wood
Galadriel:-Uma Thurman
Gandalf:-Sir Ian McKellen
Gimli:-John Rhys-Davies
Gollum:-CG (Peter Woodthorpe)*
Faramir:-Ethan Hawke
Legolas:-Orlando Bloom
Merry:-Dominic Monaghan
Pippin:-Billy Boyd
Sam:-Sean Astin
Saruman:-Christopher Lee
Ted Sandyman:-Brian Sergent
Wormtongue:-Jeffrey Combs*

  • These cast and crew members have not yet been confirmed.