From the airport you can take the 192 bus to Kipling Station then take the subway to St. George, switch to the University line, go south to Union station and it is about a 3 minute walk to the Hockey Hall of Fame. Will take you about an hour each way and cash fare is $3.00 each way.
If you run short on time, take a taxi back to the airport.
The AC international lounge is pretty decent.