Greyhounds are able to get along with cats.
Greyhounds do not necessarily need a fenced in yard, but you do have to be committed to providing them with leash walks at least three times daily. They are not a breed of dog you can simply let run in an unfenced area. Click here to find a greyhound adoption center near you. Contains a lot of great information on greyhounds and adoption. The official web site for Renewed Life for Greyhounds.