Jonty
Your living in the a$$hole of the world when it comes to hunting, fishing etc. and Newmarket isn't going to improve things. The population of Toronto and there negative influence reach's as far north as Sudbury. By this I mean Toronto folks buy recreational property and then post signs to keep everyone off it and then attempt to control the activities on all properties in the area , in regards to no hunting and shooting. There general paranoia of guns and hunting well known.
I will repeat some advice already given. There is an association in Ontario called the "Ontario Hunt Camps Association" even though I and my old camp #242 have been a members for years I don't have there contact info at hand, try Google. Anyways if you contact them they may be able to help in connecting you with camps, some of which would be open to new members. Be well aware the hunt camp culture in Ontario goes back over a hundred years. Most of the camps as stated where built on leased land that held 99yr. leases most, or all of which have now long since expired. Leases now I believe are only done on 20 year terms. Anyways the camp culture is close knit and steeped in tradition. It is hard to break in or be invited into many hunt clubs so be aware of this and be patient. Making contacts is your best bet. Also as suggested read the want add section of the Ontario Outdoors mag as several camps advertise for members in there. But if there that hard up for members that there advertising in major magazine maybe it is not that great a camp to start with.
Cleftwynd and I live in a totally different world than you, approximately 1300 miles north and west of Toronto, that's about 25hrs. of steady pound driving. And yes we are still in Ontario. When I go to Costco or need to get my heart issues checked I go to Winnipeg. Very good hunting and fishing is literally at our door step. We pay a very high price for this in many economic ways, but to most of us it is worth it, and we survive very nicely. Northern folks are a tough breed.
Cleftwynd and I enjoy our peace and quiet and what we have here. We do not encourage folks from southern Ontario to venture up here at anytime. The roads are terrible, gas prices are astronomical, the blacks flies and mosquitos are horrendous from spring to late fall when it then turns 40 below F and stays that way all winter. So your far better off to stay where you are and join a nice traditional hunt camp.