Here are your options.

CNE - not sure about this - seems to be long waits and crappy dealers

Rama - about 90 mins north of the city - one of the more popular places

Great Blue Heron - about 45 minutes north east - fairly dodgy by most estimations

Brantford Charity Casino - 1 hour west of Toronto - I like this place a lot - though they play 2-5, not 2-4

Niagara

3 options

Niagara Fallsview - higher limits
Casino Niagara - lower limits, not particularly nice, since under construction
Seneca Niagara - the best of the three - over the river in Niagara Falls NY