Mack Attack: They're both quite close to each other:
Coming North on the 400, exit at Molson Park Drive, and hang a right. 1st stoplight is Costco, 2nd is Molson Park Drive
For Misty's: Turn LEFT at Molson Park Drive, procede (at 50km/h, trust me) to next stoplight, turn RIGHT, Misty's is a few hundred metres ahead on your right.
For Hot Legs: Turn RIGHT at Molson Park Drive, turn RIGHT again at the first real street you come to (ie: not into the Costco parking lot), I believe that Hot Legs is in the 2nd plaza on your Right, its not really well marked yet, on the left-hand end of the plaza.
Hope that helps, and good luck.