For those who attended the AIA seminar Serena Chen and I presented on 11/29/10 & 12/05/10, Here are some additional links that may provide additional insight.
Some additional links to assist in study for ARE Structures
Seismic Design ..................... UBC 94 component of this link is obsolete
Retaining Walls
Seismic Design ..................... UBC 94 component of this link is obsolete
Retaining Walls