Check my website's calendar for stuff happening in Oakville and points west of TO. There's a great deal of folk activity within an hour's drive of the area. The White Oak Folk Club (in Oakville) is on alternate Sunday evenings, but the start date for September hasn't been set as yet.
One of the best clubs anywhere is in Brantford, about 45 min west of Oakville - a very talent-heavy environment. They have open stage clubs on the 9th and 23rd.