There are two river side campgrounds in SSM. Both are nice. When you are coming into town, slow down long enough to drop someone at the visitor center to look at the board and see when the next expected passage is going to be. Then you can get back to the "peanut gallery" to watch it.
Other than the locks, there is also the Valley Camp museum ship, the River of History Museum, and the Tower. The tower is not much, but if you buy the all three ticket, what the hey.... The River Museum was closed on Sundays. There is also a little annex of the White Fish Point Museum on the lock grounds. If you find that interesting at all, you may choose to run the distance to the actual museum at Whitefish Point. They seem to have a big display about the Fitz. Understandable as that was the last bid loss on the lakes, but I can't go there - I lost too many friends that day and it still hurts.
I have never been on the Canadian side, but only because I have never had a reason or time.
Matt