I`ve got the blood of the prince of Kua Toa, but when I got back to Ust-Natha I can`t find Phaere. Can Anybody tell me where she is?
I`ve been to the tavern and to her rooms but there`s no sign of her anywhere.
Cheers

Um, can't say with certainty, but I beleive she's in the temple, sucking up to matron ardulace (same place you went to get the quest.)

Hope this is right (I get confused sometimes... Probably too much time at the Copper Coronet, boasting about my adventurous past...)

Yep, Gwyddion is right, the temple it is.