The Princess with Locks of Gold is Chapter 26 of Tsubasa: Reservoir Chronicles.
Syaoran, Sakura, Kurogane, Fai and Mokona have arrived at the town of Spirit in Jade Country only to find it pretty empty. A little girl is seen holding a toy cat, but her mother quickly scolds her for being outside and brings her in. Fai says he has a feeling they aren't exactly welcome in Spirit, and he couldn't be more dead on.
Quite suddenly, the town militia approaches and demands to know they are doing in Spirit. Syaoran keeps his cool and says they're investigating old legends and buildings for a book to be written by Fai. Fai quickly joins in and declares Sakura is his sister, Syaoran is his assistant, and Kurogane is none other than the hired help. (Needless to say, Kurogane isn't thrilled about this comment.) But just as things are getting uglier, a man interrupts and reproaches the militia for acting so rudely them.
Back at the man's house, he introduces himself as Dr. Kyle Rondart. He lives in an old inn, which has many spare rooms for Syaoran and the rest to stay in. But abruptly, the door is thrust open and a man with a little mustasche charges in with an old man following. It turns out these two are Glosum - a wealthy and disagreeable man who owns most of the land in Spirit - and the mayor. Glosum is outraged that Dr. Rondart would allow strangers to stay with him when so many of the children are missing (20 to be exact), but Dr. Rondart defends them by saying any information they could give might be vital to finding the children. Clearly disgruntled, Glosum storms out with the mayor cowering behind him.
Syaoran is still eager to find out more about the princess with the golden locks and Sakura's feather, but there's no time for that as Sakura quickly faints and falls asleep again.
Sakura wakes up in the middle of the night, feeling embarrassed for falling asleep again. She gets up to make the bed, looks out the window, and sees black birds surrounding an almost-floating princess with locks of gold outside in the winter night.