A co-worker of mine has 4 greyhounds and is part of an adoption group.
You can check these places out too:
Greyhound Pets of America
800-366-1472
www.GreyhoundPets.org
National Greyhound Adoption Program
800-348-2517
www.ngap.org
She says they have really sensitive stomachs so she doesn't feed them dog food, she feeds them ground beef/ chicken with rice everyday.
Good Luck!