Did anyone watch the animated comic short stories on the I Am Legend DVD (I watched it the Blu-Ray version, but I'll assume they are on the DVD version)? Basically they detail what happened in other places around the world after the outbreak started. Do note that these stories are a bit more gory (well maybe a lot more for two of them) compared to the movie, and a bit more depressing if somehow that bothers you.
http://www.youtube.com/view_play_list?p=BBF9130ADD1982B9
http://www.youtube.com/view_play_list?p=BBF9130ADD1982B9