This is the link to the official rescue section of the national breed organization. I don't know what state you're in but there's people listed from throughout the country. They're trained in how to handle "emergency" situations such as your own.
http://www.cspca.com/rescue.htm
I have had and trained many other breeds of dogs, but never sharpei. I DO know that any dog, when stressed by a move/change in ordinary surroundings can revert and act out.
According to the "temperament" section of their website,
"Regal, alert, intelligent, dignified, lordly, scowling, sober and snobbish essentially independent and somewhat standoffish with strangers, but extreme in his devotion to his family. The Shar-Pei stands firmly on the ground with a calm, confident stature.
The Chinese Shar-Pei may be aloof with strangers."
I would guess from this that they are one of the "guard" breeds, and the dog may have been confused from the move and possibly seen the sheep as a threat to his family/home. I've trained Chows and Akitas, and can picture this possibly happening with one of them.
Good luck, and please seek professional help.
Terri