Liv Tyler would buy her own ticket....

[Lairënuriel]

article snip:
She says she is definitely onboard for a return appearance if del Toro and producer Peter Jackson invite her.

"Oh, are you kidding?" she says when asked. "In a heartbeat! I'll buy my own ticket and be on the plane in a second. I mean, that was a magical experience and it was just a once in a lifetime, amazing [thing]. Because it was so like… we knew and we didn't know that it was sort of something that had never been done before, and there was this feeling that was really gung-ho. Like, 'O.K., let's go off together!' And we just rolled our sleeves up. It really was this amazing, crazy, special thing."

article link:
http://movies.ign.com/articles/875/875397p1.html