Go to "view" then to "Extensions" and you will see it there.
Or you can go to "customize toolbar" and place on the toolbar.
Remember it only works with versions 8 or 9.
I'm working on a project, but I took a break from the project to download VideoWall and play with it. Looks like a great tool -- I'll explore it in more depth, once I finish this current project (which doesn't use multiple images in a frame...)