Do you mean authentic, traditional sushi or westernized, modern? Will you have a car? How large/small is your budget?
For traditional, quality sushi, the nearest I know of would be in the Costa Mesa area. Shibucho or Hamamori (overpriced for the location, but still fine). There is better, very traditional sushi in Fountain Valley, but it is very expensive.
For modern sushi, and more budget friendly, there is Makino (all you can eat) in Irvine by John Wayne airport.
For walking distance, check the menu at Roy's at Garden Walk. There may be some rolls on the menu.
ETA: just checked the dinner menu for Roy's Anaheim, and there is a sushi menu.