Out of Comox charters a lot of boats in the area. http://www.desolationsoundyachtcharters.com/

The Desolation Sound area is spectacularly beautiful, but quite crowded from mid july to mid/late august. Reservations or luck will be required at most of the marinas. I pass through the area and hang out a bit each June going north and then again in late August or September. The water in many of the bays is warm enough to swim in and the sunshine, especially in July and August, is plentiful. Let me know if you have more specific questions.