Tanis - I keep thinking, having seen many of his roles, Kevin Spacey could fill this role easily. He would have have to bulk up a bit, but he has a gift for role assumption, and I think he'd do fine.
Laurana - I don't know why, but Lisa Kudrow pops up when I think of Laurana. It would take a little make-up, and the role would be a little more dramatic than her normal fare... but I think she could pull it off. Beyond that, maybe Gwenyth Paltrow.
Raistlin - I'm gonna have to side with Mouseferatu on this one. The gentleman who played the elder Malfoy in the second Harry Potter was excellent, but maybe just a little too... built for Raistlin. Barring him, I would say maybe the actor who played Sauramon the White, or maybe Jeremy Irons.
Caramon - I keep wanting to say Vin Diesel, but I don't think that would be good. I think a wrestler might be in order here, like Hunter Helmsly (Triple H); it would have to be a traditional good guy (for crowd appeal), someone with obvious body-building experience, and someone with at least passable acting skills -- Triple H from the WWE would do fine, I think.
Flint - the guy who played Gimli. He's the first one I think of when I think of Flint.
Tasslehoff - Ugh... someone younger, endearing, and irritating at the same time, but with enough smarts to be obviously a mix between man and boy. Also needs to be in good shape... This is a tough role to cast. One of the actors of the other two major Hobbits (not Frodo or Samwise) would probably fill this role nicely.
Tika - A mix of vulnerability with room to grow into a competent combatant. A little bit sexy, but not weak or submissive... I vote Alyssa Milano.
Sturm - Big... mustache... stubborn... the guy who played King Arthur in
Excalibur! He'd be perfect!
Elistan - I think Patrick Stewart would fill this role nicely.
Goldmoon - I'm seeing Julia Stiles here. She's played a few dramatic roles, she's got some athletic roles under her belt, and I think she'd do well in this role. She'd need a tan, though.
Riverwind - We need another massive man for this role... but he needs to be less likable than Caramon. Some color wouldn't hurt, either -- maybe Raven from the WWE? He might not be large enough, though.
Gilthanis - Orlando Bloom... sorry... you've been type-cast, Orlando...
Fizban - GANDALF!!!
and to cover the notable bad guys
Verminaard - Here... I think Colm Feore would be excellent; he played Andre Lingoe in
Storm of the Century.
Kitiara - Rose McGowan, hands down.
Ariakas - I'm thinking Colin Farrell.
Soth - I'm sorry... I don't think James Earl Jones is the right fit for this. I honestly think Liam Nesson would fill this role well.