There are quite a few Wrath of the Lich King Talent Calculators out by now, some haven’t been updated, yet with the newest Client but I am sure they will update them soon.
A good place to get started is MMO-Champion.com.
Just click on the Class you’d like to see and a WotLK version of the Talent Calculator will load.
An other Calculator (from WoWHead) is here http://wotlk.wowhead.com/?talent
If You are looking for other Useful Information on Wrath of the Lich King, for example new Spells, Professions (Inscription), Achievements, Deathknights, I suggest these Websites:
WotLK Wiki: http://wotlkwiki.info/
MMO-Champion: http://www.mmo-champion.com/
Deathknight Info: http://deathknight.info/
Blizzard has now released their own Talent Calculator here.