I have never believed that Oswald alone killed Kennedy. The magic bullet theory just doesn't fly with me, and there are just too many other unanswered questions.
As for where I was...I was in the 3rd grade and on the playground at school. All of a sudden, the teachers came down and told all of us to line up to go back into our classrooms. They were all crying. Some hysterically. I remember one of the teachers kept mumbling something about poor Mrs. Kennedy, and how unfair all of this was, and how she had just lost a baby shortly before. None of the kids had a clue as to what had happened until finally the principal announced that the President had been shot and was dead and that we were all going to be sent home.
I remember that when I got home, it was dark, and my mom, who was in tears, had our black and white TV on, tuned to the breaking news. Everything was so gloomy, and it stayed that way until after the President's funeral.
In retrospect, I think the only other time I have ever felt that kind of collective grief was on September 11, 2001, and the days that followed.
Don't know if any of you have been to this site before, but if not, you may find it interesting. It's the Kennedy Assassination Records Collection
at the National Archives and Records Administration: