Toronto is the largest city in Canada with over 5 million inhabitants in the Greater Toronto Area. It is also the capital city of Ontario. It is a fabulous city worth visiting, with a vibrant musical and cultural scene.
Go Bloor-Danforth subway all the way East to Kennedy, transfer to Scarborough RT, go all the way to McCowan, exit, walk North to Corporate Drive 401 ramp. In fact, on Google street view you can see a hitch hiker there getting picked up
To go East, you need to reach Highway 401, North of the city centre. You can reach it via Don Valley Parkway (404), slightly East of the centre. There are several on-ramps to it such as Dundas St and Queen St, a walkable distance from the centre. Please note that you cross a deprived area on your way there (around Moss park), but it's generally safe. Alternatively (and significantly faster and safer), you could take the GO train from Union Station to Oshawa GO and then transfer to the 90 - Newcastle Bus. Go to the very end of the bus route and walk 15 minutes east to the outskirts of the city. There are plenty of houses that have driveways that cars can pull over in and pick you up.
There is a large service station off the 401 near Bowmanville
I took the TTC and STC as far as it went and hitched on a not so big cross-road where cars were joining into the 401 going east. It was easy! After three small rides of hitching on random on-ramps I ended up on a beautiful big ONroute gas-station just before Port Hope. There I easily got a truck ride to Montreal. Often I don't use signs, but - USE SIGNS hitching out of Toronto. There are a lot of beggars with cardboard signs, so it's good if your sign says were you're going.
Go Train to Oshawa and walked 15 minutes to the on ramp heading east.
Take a subway to Kipling Station,transfer to a bus 123,go all the way until the end.Just across the street from the last bus stop you will see Tim Hortons.One block away you will notice big traffic flowing to Mississauga ,thats the exit ramp you wanna put your thumb .however if you walk along this highway all the way to Mississauga center,take aramp called Cawtrha.this spot will take you down south to Hamilton and Buffalo. The last bus stop on the 123 is called Longbranch, it's on Lakeshore; if you keep on the side of the road you're on and walk forward, there's a pretty good place to hitch within your line of sight.
West toward Kitchener (Ontario), London (Ontario), Windsor (Ontario), Sarnia and Detroit
Get to the airport by going to Kipling station and taking the express shuttle to the airport, and then go to the 401 to hitch from there. Another option is to go all the way to Milton and hitching from there.
From Kitchener, one can take the 201 bus followed by the 51 bus and a 15 minute walk to get to the onroute at Cambridge. Once there, you can start hitching in either direction along the 401
North toward Barrie
Blackriding (preferably during rush hour, also train might run only once a day during weekends) the GoTrain to Barrie, hitchhike further north. (10$ if you want to pay for the ticket)
This method gets you just north of Major Mackenzie drive which is far enough outside of Toronto that you will be able to get a lift. In the Summer, you can take the subway to Yorkdale station (I believe York Mills Station works too), Proceed to the GO Bus Terminal and buy a direct ticket to Wonderland (should be $4-5). When you arrive at the park it is about a 200 meter walk back to Highway 400. There is an overpass on/off ramp right there, where you can wait for a ride. When you get off at the Park if you go in the opposite direction from the highway about 300 m there is a large plaza with lots of gas stations and fast food joints for food, including a Tim Hortons for your coffee fix. Also check the "Canada's Wonderland" website for updated info on this bus, under the heading "Planning a visit" then "Directions". If arriving into the metro from the Southwestern cities (Windsor, London, etc) in Mississauga, try to get dropped off at the Square One shopping mall. At the nearby GO Station, you can buy a ticket to the Go Park & Ride at Wonderland for $13.
Helpful Tip: try to convince the bus driver to let you off just after you get off highway 400 if you want to avoid the walk from the park back to the highway.
Alternate Route to the Park: To my opinion, the best way to get there - operating year round, cheap, frequent: take the ttc bus 165D from Wilson subway to its last stop, Hwy 400 Car Pool Lot. Buses run Mon-Sat from 5.43am - 24 to 30 mins interval, last bus at 9.51pm. If You will not get a ride north, the last bus 165D back to Toronto runs at 10.54pm. Sunday: they run from 8.50am till 8.10pm - every 32-40 minutes. You can use a free transfer from the subway, and You are supposed to pay extra $0.35 since You travel past the city border. This last stop is only a FEW METERS from the ramp! THe ramp is in a good place because it is out of the city, yet there is enough traffic on it. This seems to be the best spot to hitch north/transcanada from Toronto.
Another effective way of hitching out of Toronto Heading north along the 400: Take the TTC to Finch and Jane and walk West along Finch until you reach the ramp to the 400. You can stand on the sidewalk at the edge of the on ramp to the 400 North and avoid any legal woes this way. There is enough of a curb that people can safely pull over and enough traffic to make this feasible. I have hitched from here 5 times and have never wated longer than an hour. Good luck! (If you can get to the bass pro shop...this is a good place to start also, though it is difficult to get to off the getgo).