Not sure why you'd want to go to Toronto rather than the North Channel

..... but if you must definitely get the Ports book. It'll save you tons of time in finding marinas, places to go and see etc. Mine is dog-eared after only two seasons and I still am finding new things.
A good place to stop for touristy type shopping is Niagara on the Lake. Lots of shops and restaurants to see and if you're into plays there's a few theaters.
Toronto has lots of interesting places to go in the downtown area, depending on what your'e into, many shops, restaurants theaters, museum, Skydome ( Rogers Centre for baseball ( Blue Jays) & Canadian football), CN Tower etc. The Toronto Islands also has Yacht Clubs and places to dock, some nice park lands to explore and you could also take the ferry across to the downtown core.
Pier 4 is great for Seafood, along the harbourfront, (avoid Captain Johns on the boat). Harbourfront also lots of activities all summer long including a Jazz festival.
If you're going late July you could hit Port Credit for the Hunter Rendezvous. Check out the LOHSA site for info.
Get the Ports book and start reading it'll give you more than enough info to find and do what you're looking for.
( Glad to hear there'll be 1 less boat in the North Channel this summer when we head back again


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