From the police page set up for them:
The San Francisco Police Department is seeking information regarding a missing San Francisco family of four. On Friday, November 17, 2006, James Kim, his wife, Kati Kim, and their children, Penelope Kim and Sabine Kim left on a road trip to Seattle, Washington. The family was expected to return to San Francisco on Monday, November 27th, 2006. When both James Kim and Kati Kim did not show up for their appointments on Tuesday, November 28th, it caused their co-workers to be worried for their safety. The Kim’s are known to always keep in touch daily either by phone or e-mail with their friends and co-workers. The last known whereabouts of the Kim family was in Portland, Oregon on Saturday morning, November 25, 2006. They were driving a 2005 silver Saab station wagon with California personalized plates of “DOESF”
There are photos and descriptions and more information at that link, as well as contact information.
Their co-workers have also set up a website with info and pictures and links.
Associated Press/Northwest Cable News (NWCN) reports that police have determined that the family's cell phone and credit cards haven't been used since Nov. 25.