I am looking for a tutorial. I am editing 16x9, but I have some older 4x3 DV footage I wanted to mix with new shots. I remember there was a tutorial on line how to resize in Motion 4x3 into 16x9, but I can't find it now. If someone would post a link to it it would be great- thanks in advance

I think resizing in Motion would be way overkill for simply changing aspect ratio. All you need to do is drop the video into FCP onto the 16x9 timeline. By default it will pillar-box the footage, but you can zoom in to fill the frame, or stretch it to fill the frame.

Just to expand a little on what Edward has said... after dropping the 4:3 footage into a 16:9 sequence you will have a black bar to the left and right of the image. Select Image+Wireframe from the button at the top of the Canvas window and reduce the view size to 50% so have some space to work. You will see a dot in each corner of the 4:3 image. Grab that with the mouse and pull outwards. The image will zoom larger until it fills the width of the frame. If you like, you can also slide it up or down to get the composition you like.

Thanks for help- Robert