Miranda Otto (Dark Horizons):
An article about Miranda Otto and her role in The Lord of the Rings

Miranda Otto: Eowyn (Empire Magazine):
A short interview with Miranda Otto about LOTR.

Female characters are scant but strong in Tolkien trilogy (Orlando Sentinel):
A lovely article about the woman of LOTR. Interviews with Miranda Otto and Liv Tyler.

Emerging Éowyn: Heavy Burdens and Slashing Swords (LordoftheRings.net):
An interview with Miranda Otto from the Official LOTR website.

Warrior Princess (Starlog):
An interview with Miranda Otto in which she discusses the character of Éowyn, Éowyn's relationships, and her fellow actor, Viggo Mortensen.

There and Back Again (Ain't It Cool News):
An account of the author's visit to the set of ROTK. This includes a lovely description of Éowyn and Farmir's wedding (which I've bolded in the article).