I recall the character in the book was a nature-spirit type girl called Brown Hanna kept as the prisoner of an evil sorcerer and her best friends/adoptive family was a pair of animals. She met some guy who got turned into a wolf pup and escaped the sorcer and went on a journey to find her origins. Eventually going from Brown Hanna to Green Hanna (I think) to Gold Hanna. I just can't find it online because the name of some woman named Hanna Brown keeps popping up.
charming
"Treasure at the Heart of the Tanglewood" by Meredith Ann Pierce.
http://www.goodreads.com/book/show/691995.Treasure_at_the_Heart_of_the_Tanglewood
"First she is Brown Hannah, a drab healer living in the enchanted Tanglewood. Then, when she challenges the magician who holds her captive, she becomes Green Hannah. Next, she is Golden Hannah traveling through the land, with talking animals and birds by her side. And, finally, Russet Hannah, when she makes the long journey back to where she first grew, and learns her true story."