Igor, I'll repeat my e-mail to you for the benefit of others.
We are located just north of Guelph, which puts us 1 hour from Lake Ontario, 2 hours to Lake Huron and 2 hrs. to Georgian Bay. Being 2 hours away from the boat eliminates the summer evening sails, which I miss. We've spent many summers in the Georgian Bay region and love the area, which is why we ended up here, even though it limits us to weekends and summer holidays. Georgian Bay and especially the North Channel above Maintoulin Island, is world famous for its cruising grounds with endless areas to explore and anchor out. Our typical weekends consist of sailing on Saturday for several hours and then dropping the anchor in a protected bay and spending the night in great surroundings, sometimes with only a few other boats and minimal cottages. Sunday we sail back to our marina. This summer we are headed up to the North Channel for 2 weeks of sailing, cruising and anchoring out.
One disadvantage to being in the Midland area is the amount of boats and sometimes feeling like I'm trying to sail across the 401 (the 16 lane highway through Toronto). Midland area has probably 4 - 5,000 boats and nice weekends like this past one can get busy. However, once you get past the 2 hour cruising range it thins out considerably.
Check out this website for a good listing of the marinas in that area.
An overview of marina rates for a 30-footer on southern Georgian Bay
That site also has lots of info on the area in general. Otherwise there's lots of info on this region on anchoring locations and crusing grounds from various locations and the people up there are great. I spent the first winter after we bought the boat doing research on cruising and anchoring
Best info on the area is the Ports Cruising book. Cruising Guides