The site http://www.data.scec.org/clickmap.html has a great map of historic Southern California earthquakes. The site says:
"Below is a clickable map of southern California, with epicenters of historic earthquakes (as far back as 1812) of particular note plotted over the background topography. Shown, too, are major highways (in tan) and the surface traces of major faults (in greenish-blue)."
In the picture above, do you see the blue fault line northeast of San Diego that has only one dot on it, about where Lake Elsinore in Riverside County is? The earthquake today will be a dot about 25 miles northwest of that one dot, right near the end of that fault line.
A list for all of the Southern California earthquakes on the map is at http://www.data.scec.org/chrono_index/quakedex.html.
What was I doing? Reading, of course. Looking for blog fodder. I had Facebook open and Miriam Midkiff IMed me and we chatted for a bit about earthquakes in our memories. She went off to do her thing and I played some Scramble games, then went in and watched the TV newsers and ate lunch.