It's on (I believe) 50th and Barlow.
-If you're heading Deerfoot South bound, you take the Peigan turnoff and go through the lights at Peigan. It'll be your next right (you can't miss it).
-Deerfoot NB, take the Peigan turnoff and turn right @ the lights. It'll be on your right hand side.
-If you're heading NB on Barlow, you turn left @ 50th and right into the Road King.
-If you're going east on Peigan, turn left @ Barlow, and it'll be on your right.
I think that about covers it. There's big signs for it, so you shouldn't miss it.