I've never hunted (or fished for that matter) west of Winnipeg, but my younger brother bought a house in Portage and is moving out there next weekend. It would be a shame to visit him unless it was to go hunting or fishing! Neither of us has a hot clue where there is crown land your allowed to hunt on though.
I have hunted there many times. some is really thick bush and some is open with rolling hills. No vehicles allowed so be selective with what you shoot if you are really far off the road. never had much luck out there and it can get crowded. If you go to the provincial building in portage, that where Natural resources office is, they will give you a map of the area.